F series quality

Hello everyone
Ok here it goes , personal input please, I’m looking to purchase an F series with sound.HO scale , DCC.A unit or A and B unit together.

First off is there a differnce between Athearn and Atlas diesel locomotives specifically F series.
Is one manufacturers mobility/ realiability going to be better than the other , not confined specifically to Atlas or Athearn?
Is the sound system in one manufacturers F series going to be better than another?
Is there such thing as a really well built,smooth running good performance Diesel F series with just as good a quality sound?

I realize there are many manufactures out there each saying there the best.

Thanks in advance for the input.

Have you tried posting on the Model Railroader General Discussion ? The question of the best F7 is being discussed there now. Hit Trains.com Forums

TY , I guess that’s where I thought I was posting I’ll certainly take a gander