I'm afraid I really don't know what any of you are talking about when you say you've had problems with the wings folding on your Sky Fly's. Were the wings already damaged before they broke? When I first got mine I noticed a bit of wing flex and considered adding "flying wires" to support the wing, but decided it really wasn't necessary. I've even rubber banded my 5 1/2 ounce digital camcorder to the top of the wing and took some aerial video with it, no problems whatsoever except for a bit sluggish on climb out, and you have to land it a wee bit hotter, about half throttle or so. The video can be found here.
[link]http://asifyougiveadamn.blogspot.com/2006/05/wanna-go-for-ride.html#links[/link]
I've flown mine more times than I can count and haven't had any problems with it except for the nose wheel. Every time I would land in grass or a little rough on the pavement the wheel would bend a little to one side then the plane wouldn't track straight on the next take off. Finally after numerous times being bent back straight, it broke off. I simply made a new nose gear out of heavier wire and omitted the coil spring and haven't had any problems since.
I bought mine as a cheap and easy way to get back into flying after a several year hiatus, and for the money I don't think it can be beat. I say that if you're looking for higher performance, buy a higher performance aircraft, just keep track of what you spend because I assure you that it will be more than a hundred bucks, probably a lot more, after all you can barely buy a bottom of the line radio for the entire cost of this plane. It would be nice if it used standard radio gear, but for it's intended use, I think the plane does a pretty good job.
I agree that "loops at will" is a bit of a stretch, with a fresh battery mine will loop OK after a bit of a dive to gain speed, but after about the first minute of a flight they get pretty pointy at the top. I've never tried 7 cell packs, but I know where there are a few that I can get cheap, I'll have to give it a try.
As far as the control authority, allow me to tell you what I've done to mine. First of all, unthread the nifty little fishing line control cables from the control horns at the tail, and instead of running them through the outside holes on the horns, run them through the inside, as in closest to the control surface. This will nearly double the control throw and makes the plane about as responsive as it needs to be, it isn't exactly intended to be a 3D ship after all.
Another neat trick that worked out great for me is to replace the monofilament fishing line with something a little less stretchy. A good braided fishing line works good, I used some leftover Spider Wire that I had in my tackle box but any of the higher quality low stretch, high strength lines would work. Just tie it to the tail ends of the existing lines and pull it through, then make sure that you get it attached firmly to the "servo" wheel by whatever method you like. The best part of this mod is that the Spectra or Kevlar fiber braided lines don't stretch, and they don't get soft when the temperature rises, so after you get your tail surfaces "tuned" with the little thumb wheels, you can put a drop of CA between them and the control horn and lock them in place, that way they don't go out of adjustment every time the tail gets bumped. There still isn't a lot of authority in the elevator, but I think that was intentional. I've noticed that my Sky Fly absolutely WILL NOT stall, even with full up elevator it just glides around slowly gradually losing altitude. With power on I've noticed no lack whatsoever of rudder authority after performing the described mods, mine will turn on a dime, especially if I climb a little first to bleed off some speed, then give it full throttle and full rudder. I've flown a lot of aileron planes that won't pivot as fast.
Anyway, I hope what I've suggested here helps somebody to get better performance out of their planes. The best part of these mods is that they add no weight whatsoever, and unlike adding area to the control surfaces, they don't significantly raise the loading on the "servos", printed circuit boards have been known to crack after all.
