I would stay away from RCA and Sanyo (bad luck with their tube TV's). So between Philips (now Funia?) and Vizio, I'd go with the Vizio.
Why not Plasma? The 42" Vizio plasma is about the same price as the LCD, maybe a little less. I have a 42" Vizio plasma and have seen both the 32 and 37 Vizio LCD's. All produce excellent HD picture.
edit: I've even seen the Panasonic 42" Plasma for under $600.