David,
Unless you already have the parts to power them, I wouldn't bother unless you really want to, Trainworld I think still has the P2K FA1 and FA2 A/B sets on sale for $49.99, both powered, much better shell. You''ll spend more on each one if you don't have the parts already.
I'm the one who bought Glens FA's and I'm not doing anything with the Lionel shells although one was still powered and I painted it up in the cigar band scheme and am running it till the Lionel motor goes.
On the TM shells I got from him, I had parts to power the ones that weren't, and spending a few dollars on detail parts, that's it.
Walthers also has their FA-1 on sale for $26.98, they still show a NYC available. You'll pay that much for an Athearn F unit plus you'll need sideframes, etc.
Now to nit pick the shell, the headlight area is wrong, it sits to high up above the nose, but the roof detail is better than the TrainMiniatures.
It's your choice, it's your railroad.