These little GE's don't mesh with my modeling needs, but I have noted a few of my GP40-2W's are rather loud... the coffee grinder description is apt. They sound like they should run poorly, but they actually run quite well. The SD50/60 and C630 have scared (scarred?) me from ever buying an Atlas six axle again, and the performance of many of their four axles was sending me in that direction as well, but the GP40-2W has reversed that.
Yeah, I too am less than thrilled by Atlas locos in general. The FA I just bought needed some burnishing of the front truck pivot to loosen it up, and the brand-new engine tends to stop randomly on my layout. Now I don't keep my track sparkling scrubbed shiny bright daily but my other locos don't do this. It will need an extended run time to break in, I guess.
I've also got an Atlas RS3, a FM 16-44, an S2, and the only one that I really thought runs well is the S2. Except when you try to clean the axle points you need to de-solder the pick-up wires from the decoder, and to get them back on ---%$%%$#%#%$!!!
My roster of reliable locos are Kato, Lifelife, a Bachmann TenWheeler (with sound). And mysteriously, a old BLI/PCM E7, as long as I keep the wheels clean. The one DL109 I got in a Walthers box was really a LL from when they bought the company.
Oh, forgot the Bachmann 44T. As long as it only switches its little well-powered industrial district, it putts along very well.
