The Apline SPS-510 speakers fit perfectly in a small space, were easy to install and sounded better rounded that the Kicker's that they replaced. For a small speaker they put out a big sound that perfectly compliments my Alpine head unit, I was especially pleased with the full mids & crisp highs.
My only complaint is that Alpine should have used a metal frame, one of the plastic mounting spikes cracked when I was installing it. Alpine lauds the plastic frame as an improvement - oh really... Otherwise it was a great purchase and suited my needs.