I've got two D&H 308/762 AR10/SR25 20 round pattern mags. I bought them as an inexpensive mag to play around with but have tried them in a SR25 and Repr MK 2 and they get stuck in the magwell BIGTIME. D&H is unresponsive and apparently doesn't support their products.
These are the original generation, not the newer KAC-ish looking ones. Mossberg seems to have shipped their MVP line with 5 or 10 rd versions (I forget) so I would expect these to work in a MVP. I'll only ship them to free states so don't respond if you can't legally own them in your jurisdiction.
Sight supporters only. I'll randomly choose a winner next Thursday night (the 5th).