Originally designed to be the training companion of the Saucony Endorphin Pro, the Endorphin Speed is a lightweight trainer for long runs, moderate training sessions, and sprints. It's so light that it can also be used for racing. The Speed 5 has a new upper, midsole and outsole, and has received some updates that change its ride character slightly. The Speed 5 has also become $5 more expensive and is now priced at $175. This comparison will tell you which is the better version for you.
The Skechers Aero Burst is a great max-cushioned trainer with a smooth, cushioned ride. It has a carbon-infused H plate that stiffens its forefoot, speeding up transitions and improving efficiency. Compared to its predecessor, the Max Road 6, it has a softer but slower ride due to the new formulation of Hyper Burst Ice
The Asics Gel-Cumulus 27 is a cushioned daily trainer that can be used as an everyday training shoe for most runners of all abilities. While very little has changed in terms of the composition of the shoe, this year’s shoe felt a little flatter and less useful for anything past an easy run. If you can find the 26 on discount anywhere, I’d lean in that direction before upgrading to this new version.
The Kiprun KD900X LD+ is a good speed trainer/racer with a fun, bouncy ride for half marathons or shorter races. It represents excellent value in certain regions but is overpriced in some. Version 3 has a tweaked midsole foam that provides more energy return and a thicker midsole with deeper, softer cushioning.
The Endorphin Speed 5 is a flexible speed trainer with a nylon plate for runners who don’t want to train fast in a stiff shoe. It doesn’t feel particularly exciting or engaging but it’s comfortable and it disappears on your feet. Version 5 has a modified plate which makes the midsole more flexible and the rocker less prominent, resulting in a slower ride.