It was now or never, so I ordered my Atlas RS-2 from Fifer Hobby. The first time I ordered, the auto fill on my end was why the order did not transmit. I knew Fifer tested locomotives before sending out the order. In 3 days, it safely arrived by USPS flat rate small box. Anyway, it runs great, looks super, and pulls at least 10 mixed MTL freight cars on Kato Unitrack 11 inch radius. It outpulls both of my Atlas RS 4/5 locomotives (of course both of them have an unpowered axle on each truck). Also, I learned from this thread not to delete photos from My Gallery since it also blanks them on posts. Anyway, here are a few photos:
New Atlas RS-2 (Atlas # 40 004 607) pulls good:
Old Atlas RS-4/5 (Atlas #42305) also pulls good, but not as well as the RS-2:
Late Atlas RS-4/5 (Atlas #40 003 055) pulls 7 cars and starts slipping on 9 cars: