I just bought an Arch Rival suit. I really like IR's gear. I previously owned a Typhoon Multisport 3.
I have written an initial review here https://kayakjournal.wordpress.com/2...nitial-review/
I have now used it a bit and I really like it. I find it mostly as easy to move around in as the front zip Kokatats, though the zip closure is more noticeable due to the double zip.
The Kokatats are really good, but whether they are worth double the price of the IR is a different debate. My girlfriend bought a Kokatat Meridian at the same time as my Arch Rival. That suit is really nice, and the zip is lower profile. But build quality wise the suits seem pretty similar, as is the thickness of the material.
One area you do lose out on with the Arch Rival is that there is no reinforced material on the forearm/elbow and knee area like there is on more expensive suits, although the Arch Rival is still reinforced at the seat.