I would have thought that the question would be 'what is the best bearing arrangement for reciprocating parts' - if you look at a classic cylinder arrangement for example, the piston rings form the 'bearing', they flex and make the tolerances between the cylinder and bore less critical. In pneumatics, 'O' rings are sometimes used.
I would have thought that the optimal arrangement was a compliant sealing/bearing medium which is rated for the duty cycle and environmental conditions.
do not forget the opperating temp. you will have a diferant exspanssion between the piston and the cyclindar unless they are the same alloy.
you need to figure this first, then make sure your seal can handle the growth
also, if this is a air compressor, what climate will it be working in, hot and dry
will cool faster than hot and humid! so your opprating temps may go up.