Have the unit can only test for a bicycle tire - as a function test. Since it worked impeccably. The compressor is but (very) loud and I personally was missing a few additional essays (z. B. for normal bicycle valves o. Ä.). Therefore, only four stars. Would therefore probably be able to take the cheaper option. Will say: expensive is not necessarily better (here quietly and expediently). But can not compare with other devices it. In any case, it is small and convenient, and more than work, it does not have to, yes.