My former trainer has an Exiss 3-horse slant with living quarters, and based on what a brick sh--house that one was, a pair of her boarders bought an Exiss 2-horse. Both very nice trailers, both see very regular use and are holding up well to the work.
I just got a new trailer yesterday!! yay! we were deciding between an exiss and a cimarron(sp?) and for a number of reasons decided on the latter. The guy at the trailer dealer said that he preferred the Cimarron to the exiss bc of little details... like all stainless bolts and what not- the exiss we were looking at was an older model ('00) so this may have changed. But with that in mind he said he still thought it was a perfectly fine trailer, safe, and held up... the one we looked at was in great condition for its age.
I know some people who have them and are very happy with them. However, I also attended an equine rescue lecture where we saw a picture of an Exiss trailer in which a horse had flipped his head up and put it straight through the roof because the material is so thin. I just remember thinking... heaven forbid you got in an accident with a trailer like that, seems like it would do absolutely nothing to protect your horses. Unfortunately, there isn't much data out there about comparative trailer safety that consumers can use when making their decisions, so there's not much to go on except for anecdote.
My roomate has one that is 12 years old and still looks fabulous! It sees moderate to heavy use and has held up wonderfully. Horses load easily and trailer well in it. It is a 3 horse slant step up. Highly reccomend these trailers!