Have them both ways. I really prefer the bushed bores for oil control, but like I said earlier when the block gets hot, you're loosing some of your press fit with the bushings. I've been lucky so far and never had any move, but I have seen blocks where they did. Some shops will mill a half groove in the bushing and then once installed drill along side the bushing and put a roll pin in.

As far as wear, the bare aluminum bores get so much oil I've had no issues as yet. Ampco bushings are near indestructible.