Which brand is better among car audio ?

They're both really good, priced about the same, but I would go with Alpine

Across the board, would have to say Alpine. No knock on Pioneer, which is also very good in car audio.

Both make very good head units. But, I'd have to give Alpine the nod on speakers, subs & amps.

I have Pio and would never sell it. It is pretty adjustable (HPF,LPF,EQ) with nice presets. better than alpine. It can receive radio cleaner, and it looks nice.

But I guess Alpine sound quality is at least the same, and you can like the alpine design more.

If you can have nice adjustable amplyfier/s and good speakers with crosovers included, go for the alpine. If you donť have enaugh many, you can save it because pioneer can adjust it all perfectly electronically, so you can buy poorer speakers without crosovers.

I'd say get an alpine so you can say things like "Yo I got this bangin Alpine"