I have an early ARB portable compressor and Thumper compressor. The Thumper is about 3 years old and is the one I mainly use, as it is fast and robust. The ARB is my spare that I also take everywhere. It is reliable but very slow in comparison ( like watching grass grow ). I think the Thumper is very good value for the money @ about $99. It has rated well in every comparison test I've read.