what sort of age of car do you want to work on?
ive got a MT2500 snap on scanner and it can do most things, i have got a ford POD up to 2001 and it covers cosies, RST and newer with right connectors.
depends on what you want to do with it and how much you want to spend.
Ive had mine 12 months now and not regretted it at all, may look at updating it at some point maybe but for now the £400 the whole kit has cost me isnt too bad!