ive had 2 jl 12" subs and a jl 15" sub(running off a presion power mono amp), all have been stolen but while i had em i was v pleased with em. They can really thump out some 'deep' low, satisfying bass lines. Im not too sure about the infinity subs, but i havnt had a good listen to any tbh. I think its best to see what you get for your money as neither option is going to be cheap.