I can see where the 20 gauge would be nice for the rabbits. It could definetely be your work horse. A few years ago I got a "deal" on 16 or 18 boxes of shells. All were good 12 guage except for 4 boxes of 20 guage. I tried to get just the 12 gauge but the seller insisted that it was a package deal. We finally settled on a good price and in the end I passed the 4 boxes of 20 guage to my friend. He was happy for some free shells. was in wallmart last week and once again there was a really good deal on 12 guage.