A smaller diameter basket means that water travels through more coffee before exiting the basket. Because of this there is a noticeable flavour difference. Aside from 58mm ive only tried a 53mm la spaziale. I prefer 58mm but i do know someone who swears by the smaller basket.
My rule of thumb to get a better extraction from smaller baskets was to take off a second or two from the ideal extraction time. The tastiest coffees ive had from a 53mm basket were in the 20-23 second range. Could have been the specific coffee i was using however. I havent experimented with it further than that so i cant be of much more help