Hey guys. Just gauging which is the best to upgrade first for sound quality, head unit, or speakers (with amp). I understand the standard head unit has a preout so you can just plug a 4 ch amp and upgrade the speakers? As ive pieced together the fronts are 6.5" and the rears 4", is this correct? Any other advice would be great, brands etc? (Ive always liked alpine) not after chav bass just a nice frequency spread and punchy.

I'd say for overall SQ, the amp and speakers but for easier results as a first step get decent h/u with a good set of EQs on it.

If you go the amp/speakers route don't scimp on the amp. 2x150 watts would be a nice to have and a reasonable brand. Mine's a profile 2 rated at 2x75 watts and it's not quite ballsy enough.

Go for a new head unit.....you can have the best speakers/amplifiers going, but if the quality of the signal getting to them isn't the best, then they cannot improve the quality. A decent head unit should be rated at 4 x 50w with a decent internal amp, which is enough to get more out of the standard speakers before you think about adding an amp....Also look for a head unit which has a high pre-out voltage, or at least enough to match any future amp you buy as this also makes a big difference

Ive been checking out HUs thinking double din ones look neat as others have said there is a gap between the cubby hole with single ones. So was looking at these 2, my last HU was Kenwood and was brill anyone have experience with JVC?

Here are the 2

Kenwood

http://www.amazon.co.uk/Kenwood-DPX404U-2-DIN-Receiver-Inputs/dp/B004JHY2YK/ref=pd_sim_sbs_ce_1

JVC

http://www.amazon.co.uk/JVC-KW-XR611-Double-Ready-Radio/dp/B003E6VEKW/ref=pd_sim_sbs_ce_2

I'm in the same boat as yourself, and have been looking at the Kenwood 404u, as above. Similar spec to the JVC, but I prefer the Kenwood and will prob be buying one ASAP! (Think the Amazon price is more or less the best too)