There are a lot of reasonably priced BPSs out there- Mossberg 590s are about the same or more. I'd say it's a question of preference more than price. Try both, at least handle both, before making up your mind.
lpl
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BPS Hi Capacity on GunBroker:
http://www.gunbroker.com/Auction/ViewItem.asp?Item=140851187 NIB Buy It Now $399
http://www.gunbroker.com/Auction/ViewItem.asp?Item=140461394 No Reserve
http://www.gunbroker.com/Auction/ViewItem.asp?Item=140925798 NIB BIN $370
http://www.gunbroker.com/Auction/ViewItem.asp?Item=140933522 NIB BIN $349
lpl
=======
BPS Hi Capacity on GunBroker:
http://www.gunbroker.com/Auction/ViewItem.asp?Item=140851187 NIB Buy It Now $399
http://www.gunbroker.com/Auction/ViewItem.asp?Item=140461394 No Reserve
http://www.gunbroker.com/Auction/ViewItem.asp?Item=140925798 NIB BIN $370
http://www.gunbroker.com/Auction/ViewItem.asp?Item=140933522 NIB BIN $349