Les, I bought a Sealey SA22503 from e-bay as a refurbished unit. I picked it out as it has a high output, 12cfm for the size of 50L. It will run off a 13A plug and is fairly quiet.... ish. It will keep up with most air tool tasks. It outperforms my cheapo second hand draper 8cfm hands down.
I wouldn't hesitate to recommend a 50l but with a higher cfm as the air buffer is adequate for small tasks. I couldn't accomadate a larger tank either, the direct drive pump does get warm with extended use. If you can afford it though or need it for higher duty cycle go for a belt drive.
I run, air die grinder, air needle scaler, air saw, impact wrenches, inflator, blow off guns, chisels.