The Rival 310s smaller shape makes it less ergonomic; its a little more comfortable than a Razer DeathAdder, but not as comfortable as the Rival 300. 3/4" bit left just the right amount of space, and I like to sink mine a little deeper than flush so going just over 3/8" deep was just right for me. We had a leak get through this mattress protector. It paired very easily with my phone and laptop. Once I break them in this might change but right now, I feel like its just cutting off blood flow. Sole is soft and has a bounce but seems firm enough it will last a while, probably not for hardcore runners though. Once your feet get hot, they do slide about. I ended up liking the over door mount though. I dont know how these will hold up over time, but theyre decent quality for the price. After a month or so the sound started to crackle a bit (only when held in certain positions), but after a bit of fiddling with the wire the sound comes out clear again.