I own two Real Sword AEGs (SVD & Type 97), and I've used several of their Type 56 rifles. They are without a doubt the best airsoft AK clone that I know of, and their price may seem high, but they make guns that cost $50 less look silly by comparison. They're deathly accurate, insanely realistic on the outside, and impressively overbuilt on the inside.
As stated above, they can be a bit picky with other brands of mags. If you do purchase one, I strongly encourage you to be careful doing any disassembly work (or have a competent tech do it) so you don't let the magical mystical fairies out.
And like Twigg implied, truly the only wise reason to take one apart is to put a weaker spring in it (wooo, shootin' a bit hot outta the box).
Since they're not being made any more, good luck finding a new one in stock. Let me know if you do.
Not sure if you've seen
this accuracy test video