I have the Comp model and love it. It's a great bike, but I don't use it for errands though. I built up an old MTB for that task. The tricross is a great bike for just about everything though. I will say that it was quite a bit slower than the road bike that I use to have. The road bike (Eddy Merckx Ti) was very quick off the start and would hold turns like it was on rails and that's something I don't feel with the Tricross. The Tricross does great on long rides as well. I've done several centuries on it and felt fine afterwards.
Theft is a big issue and will only get worse as metals become more sought after. If I couldn't bring the bike in with me, I would seriously consider getting something for the task that you don't mind losing.