I've just ordered from screwfix.com (in the UK) a Wolf Cherokee 25 compressor for £79.99. Well the basic specs are:
8 bar max
24 litter tank
Water tap
1/4" BSP thread outlet

Trouble is it weighs 23kg and runs at 92dB when filling the tank, but I guess 24 litters will spray a lot of 1:72 vehicles

Now this was only £10 more than my Revell Gamma (I think its 2 bar or so max, with virtually no air tank - I think it only has one to stop air pulse & you certainly can't spray from it as a reservoir) and is about half the price of any branded (Revell, Ripmax, etc) compressor of a similar spec that I have seen on any model shop web site.

Just shows what you can do by looking around and I can’t believe that Revell can sell similar compressors for twice the price.