Misinformation? I highly doubt that, considering I have had nothing but success with my WE and so has everyone else that I know that uses one. Now I have replaced my entire trigger mechanism to steel, because some parts have shown signs that suggest that they are beginning to ware out. This is because there is over 10,000 - 12,000 rounds through mine easily. Before you say that's rubbish, I plink as well as game; skirmishes and milsims, but I'm going to stop this right now because this thread will just turn into a fanboy WE-is-better or KJW-is-better thread.
The OP is also most interested in the 416. You can find them, they just might be more expensive. WE is the only company which made a gas 416, unless VFC has released theirs already.
To the OP: with regards to the WE, you will not find that many after market bodies. There are only a select few, the most popular being the blank receiver or a COLT M4A1 receiver, with the exception of the 416, and T91 receivers. I also do find with all WE's, that they have the best looking externals out of the box (my opinion). However the rifle is built to Real Steel spec. So all real steel parts will fit, this includes rails, flash hiders, stocks, sights, gas blocks, charging handles, grips, buffer tubes and even upper receivers if your willing to do some modification to the lower.
Now I am not putting down the KJW, it is a great performer, and decently accurate, as well has excellent cooldown, but it lacks very little after market support for things like receivers, and internals, but will take AEG front ends and externals, which is a plus if you wish to keep the hit on your wallet less painful.
Lastly I would stay away from WA/G&P WOC magna systems, as they have a history of one part failing after another. If you are just interested in buying a gun for plinking, and it appears to me (no offence) that you have very little knoweldge in GBBR's (hey its a great time to learn! and i'm still learning!) I don't think that you want a gun that you have to keep fixing. There are members here who can help you with the WA/Magna system - I think Kullwarrior knows quite a bit about them.
As for VFC I have no experience with them what so ever.
If you decide to go the WE route, you will have fun with the magpul parts, as their real parts are not as expensive, as say Troy or Daniel Defence, and the real steel magpul parts will fit! There are quite a few online retailers that sell magpul parts. I believe
www.oneshottactical.com sells a few magpul items. Your best bet is to go over to
www.canadiangunnutz.com, as they have a slew of retailer websites that sell real steel accessories, including magpul.
With GBBR's your going to spend some money, it's going to happen, regardless of which one you buy. I look at it as having one hell of a cool toy to play with afterwords. Have fun!