I have a 870 in 12ga. and have fired my friends 88, and besides the 870 "feeling" better made, there really isn't much difference. Also, I don't think the 12ga is a must. If you can, get her to a range and test out the 12 and 20ga. If not, well, maybe a 20ga wont be so bad.
Also, the Maverick 88's ain't a bad gun, but beware that some models were not made with a majority of Mossberg 500 parts, therefore are not compatible with the 500 accessories. Of course, like someone said on here already, there really isn't much you need to put on there.
On my 870 I put a M4 style stock on it due to my wife not having the arm length that I have, so with the stock shortened, she can control it alot better. Don't know if the 88's have that option or not.
Hope this all helps,
Official Adrenaline Donor
1971 Chevy C-10 LWB - 350/350 with some fun parts.
1999 GMC 2500 LWB
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