I bought a 60amp one to try as a ginuea pig. I haven't had any problems with it in a xxt with a 380 size 4800 L can on 3s. I don't really know what I am feeling, but something midway on the bottom of it gets pretty warm, quickly, but doesn't get any hotter as you mess with it. The heatsink doesn't really ever get hot. It seems to work really well. It does kind of bother me they don't have a warranty, so if it doesn't work, and fry's on 5s, could have used the money to go towards something better. I just ordered one of the 100a versions. Kind of a gamble I guess. Here is where I bought it from, I am fairly sure it is the same controller you are looking at. Made them an offer they couldn't refuse I guess! I already had the programming card from when I bought the 60 amp, so It was cheaper for me to get it from here. On you first one I think you'll come out ahead on the other one since it comes with it. The program card in the redflag auction looks just like mine.
http://cgi.ebay.com/67G-Programmable...713.m153.l1262