quick question bout primer

All over in the FAQ it says that primer is a must, and everytime i see you guys do models, you all use primer.

What kind of primer do you guys use? I need something that doesnt fill in, because wont that fill in around little details as well?

Tamiya surface primer in either white or grey

It will only fill in details if you spray it on too heavily, just the same as any color quote would.

I use Tamiya primers mostly, but also Duplicolor automotive primer.

If you are shooting enamels (like Testors for example) over a stock unmodified body, I'd skip the primer. If you are using lacquers (even the mild Tamiyas) you'll need a primer for adhesion and for some of the more aggressive lacquers, for protection against etching.
I like the Tamiya Fine White Primer. It's thin and usually there is no need to sand between priming and painting. Gunze Sangyo has some too that are very fine. Also Krylon gray works well and is cheaper, but is much heavier. - Mark

I can't get tamiya primer in the uk, so i use halfords plastic primer.

I use GSI Creos (Gunze Sangyo) Mr Surfacer. It comes in different "thicknesses". The 500 is great to brush on and fill small surface imperfections the 1000 I airbrush as a primer. As mentioned above the trick is to keep it very thin, which is easy with an airbrush but possibly a bit trickier with a rattle can. GSI Creos also have a new Mr Surfacer out, 1200 that I guess is even finer.

I use Duplicolor Automotive White primer and Varsity Automotive Primer. Avoid Testors or Model Masters primer.

I use dupli-color primer to, it goes on nice and thin