Will this be a good car sub?

They would be a good match, but make sure you get the 4ohm version of the sub, if you get the 2ohm version it will be way overpowered. Although that is a pretty decent amp, for cleaner/deeper bass you would want an amp with a 24db crossover; BUT a 24db crossover tends to reduce some of the punchiness in rock music (it's a tradeoff). Anyway, overall for a "starting out" set-up, that amp and sub would be a good choice.