I voted for rats, because you also asked for which is least high-maintenance.

I found that I simply didn't have much luck with ASFs. I tried everything. Food, temps, new colonies with fresh bloodlines, but it just wasn't working out for me.

I found they take WAYYYYYYYYY too long to hit sexual maturity. It's usually at least 3-4 months before they will breed and have babies (females, anyways). Then it seemed they would breed well for awhile, and then all of a sudden just come to a grinding halt. POOF. One day, nobody was pregnant, nobody was having babies. I fed them all off and breed regular rats now and their production is INSANE compared to the ASFs.

Perhaps if I had more space to stock pile grow ups, I could have rotated my breeder ASFs every few months and had better production, but I didn't so I quit breeding them.