I just picked this thing up in the mail today after buying it. I bought it because I want to be able to use M4 mags in my G36c, and this is the best conversion from what I hear. Here is what it looks like:
The left side. The new mag release button is clearly visible.
The right side. Nothing special here.
"Private Parts Airsoft" is clearly visible on the right side.
BUILD MATERIAL:
This conversion is made entirely out of a mix of fiberglass, ABS plastic and other materials of the sort. It's very strong. So strong, that when I first picked this thing up I thought it was made out of metal and coated in plastic. Compared to the stock magwell, this feels much heavier too, which is a plus for me.
THE BAD:
As great as this conversion is, there's one thing I HATE about it. The hole where the nub the magwell pin screws into goes is WAY too small. It will most likely take intense sanding to get it to fit, but since my nub is stripped, I don't need to bother. I still consider this a con because the pin can easily fall out in the middle of a skirmish now.
CONCLUSION:
Personally, I love this. I haven't gotten a chance to use it yet, but my friend is coming over tomorrow and he has an E1 M4 midcap we will try it out with. From what I can tell from comparing it to the stock magwell, it should work well. The seam on the loading port thing (I don't know the correct name) is split just a little because I bought this used, and it seems a little shorter than the stock one, but I don't think it's enough to make a difference though.
USEFULNESS: 9/10
ATTRACTIVENESS: 6/10 (I think it looks pretty cool, but most people think it looks ugly)
QUALITY: 8/10
COST: 7/10 (this conversion costs around $30-$40 on most sites, and you get what you pay for)
OVERALL AWESOMENESS: 7/10
TOTAL: 37/50 or 74/10 (C)