Browning is going to be making the A bolt slug gun again for 2011. Definately worth a look, but they are not going to be cheap... msrp around a grand... probably be found for 850-900ish. Still though, you can buy a pair of 220/212s for that kind of money.

I'd personally rather have a 12 gauge than a 20 as the 12 is flatter shooting and carries a heavier payload. But either will do the deed just fine.