Shoe Review: Pearl Izumi Streak II (Women's)

Meet the Pearl Izumi Streak II. Lightweight, breathable, supportive, comfortable and sturdy. After more than a hundred miles (including running a full marathon, a 10K and a 5K in them), I am loving this shoe. Below, you'll find a comparative review of Pearl Izumi's isoTransition and the Streak II, but first, here's the low-down on the Streak II. 

Of course I got the pink ones! I just love the smell of new shoes right out of the box!

Moisture-wicking mesh is everywhere on this shoe. The midfoot mesh is structured for more support, with more flexible breathable mesh in the forefoot and tongue. Midsole drainage holes help keep your socks and feet dry.

Breathable design made possible by moisture-wicking mesh and  midsole drainage holes
(Ortholite liner removed in this pic).

Note 2 different types of cushioning material here

Thin Ortholite liner provides added cushioning for long runs.

The sole of the Streak II has lots of segmentation in the forefoot, lending itself well to a controlled, natural and smooth transition through the landing phase to toe-off. The cushioning in the rearfoot is carbon-based rubber which is important for durability while the forefoot has an extremely light, cushiony blown rubber sole.

Toe box width is always a concern for me. I need room to splay my piggies! The Streak II doesn't disappoint with a very comfortable and flexible toe box.

The Streak II is marketed as having a seam-free interior. This is mostly true with the exception of the spot where my finger is pointing. Inside the shoe at this point is where you can feel some fabric bunching (top of the interior - NOT on the interior sole). I'm assuming this is where a few pieces of fabric needed to be sewn together. The isoTransition has a completely seamless interior. This being said, this has had zero impact on my comfort level with the Streak II and after 120+ miles, it has not caused any discomfort what-so-ever. I wouldn't have even known that area existed if I didn't plan on writing this review as I had not felt around the interior until now.

The exterior forefoot is seamless with a bonded upper toe cap.

This bruising may have more to do with my running form and/or the extremely steep inclines and declines on the Nike Women's Marathon course , but I have not had this happen with other shoes or even after other long runs in the Streaks. This is the same foot that overpronates (much more so than my left foot). I am certainly not suggesting the shoes "caused" this but I always like to offer more info than leave something out. Long distance runners know toenails are for sissies anyway, right?!? ;-)  It may look a little nasty, but was not painful or even noticeable to me.  I wouldn't have even known this bruise was there if I hadn't taken off the toe nail polish.

Found this under my toe nail polish a couple of weeks after the NWM.  

This past Sunday, I set 2 course PRs at the Calabasas Classic wearing the Streak IIs. I have never seen a running picture of me (or any picture for that matter) where I'm riding the outside of my foot. I'm a high-arched overpronator. Where is this supination coming from?!?  I think it's likely a combination of running a lot  faster that I have been in months; I ran the 5K and the 10K consecutively on this very hilly and tiresome 5K loop (the 10K started 35 minutes after I finished the 5K); and it's a fast downhill finish.

I set 2 personal course records at the Calabasas Classic in the Streak II.
5K - 24:45; 10K - 55:08

I think this is my 10K finish. I do remember feeling a little off-balance at the end of both races but that has more to do with me controlling my legs and feet than it does with the shoes. I was feeling every part of the road I wanted to, but I do need to keep focused on my foot placement at higher speeds in these shoes, especially when my lower body is feeling so taxed.

The isoTransition versus the Streak II:
You can read my full review of the isoTransition here. These models are VERY similar. The difference is that the Streak II is designed to be comfortable for longer distances. I have yet to run further than 7 miles in the isoTransition (and I don't think I will), but boy are they FAST!

The Streak II has additional cushioning and breathable mesh material in the tongue and heel. Ideal for longer distances. The isoTransition is more like a true racing flat. Hence the thin lining in the tongue and the interior of the heel.

The isoTransition has the heel pull in the back for easy slip on-off. Both models have structural overlays (black strips you see here in the heel) for more support without added weight!

The exterior outer soles are also identical. Carbon-based rubber in rearfoot (higher wear and tear areas); spongy, lightweight, energy-returning foam in the forefoot.

The lateral structure of these models appear almost identical. Both models feature a structured midfoot mesh (combined with the structured overlays) with a high breath-ability factor and a very flexible forefoot. 

Lateral view

The instep is similar between the shoes, however, the toe box cap in the Streak II seems slightly thicker to me and wraps further around the toe box without adding weight (accomplished by using blown rubber). Note the addition of the TPU (thermoplastic polyurethane) shank in the isoTransition for increased medial support and stability.

Medial view

Both models have the same stack height (heel/toe ratio) and weight:

• Heel/Toe offset - 19.0mm/10.0mm (9mm offset)
• Weight - 7 oz (Women's size 8)

Both feel true to size, but consider this:

• If you like to have a roomy toe box (due to excess swelling during long runs, etc), I can see how buying the Streak II a half-size up would be more comfortable. 
• If you're an "in-between sizes" runner with most running shoe brands/models, I recommend bumping up to the larger of the two sizes in BOTH of these models.

Primary differences
The isoTransition:

1. Quick lacing system (bungie laces)
2. Heel pull for quick on/off transitioning
3. Midsole TPU shank
4. Perforated midsole (in the Ortholite liner; not just the outer sole)
5. Extra energy foam compound in the forefoot for added cushioning (not visible on the exterior)
6. Truly seamless interior for a sock-free racing experience
7. Bullets 1-3 make this shoe ideal for Triathletes

The Streak II:

1. 360 degree lacing system for additional midfoot hold/support
2. Thicker forefoot, collar and tongue mesh for added cushioning and comfort
3. Designed to go the distance!

Based purely on 'feel', the isoTransitions feel like slippers to me. They are so lightweight, comfortable and easy to slip on and off. I rarely step outside in my running shoes without the intent of running, but I wear the isoTransitions just about anywhere!  Stepping into the Streak II feels more like putting on a running shoe and I guess it should given the lacing system and the thicker cushioning around the heel and tongue. I feel like I could run forever in the Streak IIs. This is not the case with the isoTransitions. BUT, I can definitely tell you my feet turn over faster in the isoTransitions. If you're looking for a shorter-distance racing flat that feels like a ballet slipper with a little more structural support, go for the isoTransition! These are also great for speed work. Add in the Streak II for your longer distance training runs and races.

I have already ordered a second pair of the Streak II's AND a new trail shoe, the PI Peak XC!! I'm very excited to try these trail shoes.

Happy Running!