I currently have two PS3 locomotives--one RailKing and one O tinplate. I'm not anywhere near the "decibel counter" (equivalent to rivet counter) that some are, so can't really offer much of an evaluation related to the sounds. Both seem perfectly fine to my ears.
The primary PS3 advances that most interest me are the absence of an ugly tether, and the absence of a battery (and the need to get to the darn thing). Personally, those two features alone have pretty much convinced me that I will henceforth be buying very few, if any, earlier PS2 locomotives (thereby single-handedly killing the PS2 market).
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