Hi there - i have a tricross and have tried a couple of different racks on it and used it for a couple of different things so hopefully this'll be helpful
i'm kind of large (6'3"/235#) so your experience couple possible be different.
When i first got my tricross i put a Jandd "standard" rack on it. It fit perfectly but didn't allow me enough heel clearance with my panniers so i returned it for the expedition rack. I wanted to use the bike for occasional runs to the grocery store as well as my normal small riding-around-trunk-bag.
The Jandd expedition rack fits perfectly but maybe looks a bit out of place on the bike as it's big, squared off and kinda burly. Perfect in my book
, and the heel clearance issues were gone.
Two loaded panniers on the rack (on any rack i presume) is not this bike's sweet spot. in fact it's rather dangerous, or was to me. It sagged a little (frame flex) just with the weight on the rear and trying to get home was an interesting experience. I then knew what people speak of when they talk about a bike riding like a noodle. This was a noodle that had been soaking for a few days. Anyway, that was the end of that.
I removed the Jandd Expedition a couple of days later and replaced it with a Topeak Explorer rack which also fits the bike fine (and doesn't look super out of place either.) I picked up a small Topeak trunk bag with these zip down "panniers" and will only use it on the bike. It's not big enough to put too much weight in but can still cause noodling.
Bottom line, and this is just my experience: i'm pretty confident that any rack designed for a 700c tire will fit on the rear of the bike - the braze-ons seem to be good quality and i got nothing but a secure fit with all of the racks i tried. But be careful with the amount of weight you plan on carrying with it. For me a couple of sandwiches, a bottle of beer and some clif bars are the limit on the weekends and a pair of pants and a shirt will do it for me on the weekdays.
Don't know if it matters or not but the bike is an '08 TriCross Comp (Alu/CF) in a 58cm