I bought a Kangke Laser 2000 a few years ago. ZDZ 60 engine.
The engine sucked--but when I finally dumb-thumbed the plane into the dirt about 2 months ago--I went right out and bought a new one within a week. I liked it that much.
The Kangke quality is pretty high IMO. For a Giant Scale ARF under $450--it's top notch!!
I bought the MW 40 size Ultimate too. I thought the little wing templates were a really nice addition to the box. How in the world would you ever get the incidence right without that little jewel? The quality is very good--which is typical of World Models.
My worst experience so far has been the Seagull 40 size Decathlon with 68" wingspan. It's a pretty nice ARF--outta the box. Tail pushrods are installed. Covering and framing is very good. Design is very good.
My problem with this model was quality control. Silly me

I expected the incidence to be correct on a factory built model thats most likely built in a jig. WRONG!! I made a rookey mistake and didn't check the incidence untill AFTER I flew it and discovered that the horizontal stab was pretty far off.
I don't know how I would have fixed it. With a H. Stab that has 4* positive incidence--what are ya gonna do? I couldn't hack the stab out--that would have menat a total rework of the rear end of the plane--even if I had caught it before I glued the stab on. What are ya gonna do with it?
I could have reworked the wing saddle--but that would have also meant stripping the covering off and sanding the saddle down to make it match the tail. Neither option was acceptable to me.
I should have known better than to just slap it together without dry-fitting it first and checking the incidence.[:@] But, you'd think it would be built close enough to at least fly
decent.
Thats my only real complaint about ARFs. I've bought cheap ARFs and I've bought expensive ARFs. I find that the best quality comes from the ones that are priced right about in the middle or slightly higher end for sport fliers. I wasn't really too impressed with the quality of the very expensive ARFs. Decent--but not worth the
extra $150 for a 40 or 60 sized model.
I'll never pay $750 or $800 for a 50cc sized model. I really can't see the quality being THAT much more than a $400 or $500 model. $250-300 is a LOT of money. For that much of a price difference--that 85" model thats designed for a 50cc engine----it better weigh 13 pounds RTF with an average 50cc engine and it should have 1450sq.in. of wing. To my knowledge--none of them fit that criteria.
I don't buy the stupid cheap ones anymore either. They just aren't cheap enough for the quality you end up with.
Overall--I think that with the huge volume of ARFs on the market--your bound to find a turd now and then. I think that about 90% of them are pretty decent.