I have a sig xtra with the OS160 and an 18x8 pro-zinger. Flies well, but just as DV said, it doesn't sing any 3d music because of the weight. I've seriously comtemplated stripping it down to try to shave some lbs. Right now, with nimh batt., hitech 605's (and a digital on rudd.) it weighs 13lbs. 2oz. I get plenty of vertical for IMAC (intermediate) but it suffers on uplines on a windy day. If my wife hadn't personally bought the xtra for me, I would dump it in a minute for a capX. Still though, the xtra flies real straight for precision manuevers. Hope this helps.....