Originally Posted by Ira in Chi
The Rush, built with Reynolds 631, is lighter and has thinner tubing which I have found makes for a comfy ride. I am consistantly pleased by how supple yet stiff it feels on the street, you get a lot of bike for your money. It is designed as a "track bike for the city", whereas the Mark V is more of a fixed gear roadbike (has cable stops and a more relaxed geometry). The Mark V has an amazingly low price which makes for a great value. If you are used to traditional road geometry, the Rush will feel more responsive. IRO has a great reputation for customer service, and Soma has never responded to one of my emails(Boo).
the soma rush is .3 pounds lighter than the iro mark v. im getting that from the websites. the soma list theirs at 4 pounds. iro puts theirs at 4.3. that's about a 130 gram diffrence.