There is nothing as 'best' in car audio. What sounds good to your ears and has decent reviews i.e. no really strong, negative reviews, will be the best for you.
Having said that, I would advise that you first determine your budget, after doing a bit of research on the WWW. Select the 'best' components that your money can buy and get it done from a professional installer.
I am listing some good brands to consider at each component level:
1. Pioneer - VFM
2. Alpine/Eclipse - expensive but worth the price
hi guys you had completely forgot one world classs brand which is
FOCAL speakers.ITs a bit expensive....but if you use a alpine player with focal as the frount speakers ..it sounds amazing for music freaks...,...check it out in neared store..trust me it sounds amazing...