A Life Like diesel for $12-20 from model expo is a great deal, but that isn't the original price. The new run of Life Like engines are $90 MSRP! I hardly think they are worth that, the new price is right up there with Atlas and Kato. I bought 10 of the GP20's from model expo for $15 too, and I love them, except for the non dcc ready frame, but I don't think I'd pay over $40 for one. The new GP60 does look really nice... the EMD scheme might look good on the layout!
-My favourite is Kato, followed by Intermountain, LBF and Red Caboose, then Atlas.