I'd be leary of transmissions over 130-150k, the tranny is deff the weak point. The wheel bearings suck, and they will leak coolant from the little bypass tubes because some dumbass engineer decided to run coolant through the alternator bracket (really a pretty easy fix). The engines are great. We bought our N/A 3800 Impala with 30k and it now has 170k, basic maintenance, a radiator, a MAF, and a tranny (just 6 months ago), and it's still running good.