AC vs DC traction motors - pros/cons?

I retired in 2001, so have no recent experience. I suppose that the GE guys "tweak" the software also. I do know that at the time GE developed slow speed/flood loading control for the AC4400's, they tested with multiple GE AC's and also with DC units. In addition, they tested on various railroads in actual flood loading service. I assume but cannot confirm that GE tested mixed GE and EMD consists.

There were no "unusual situations" seen during this testing such as "wheel chatter". I have no recent knowledge re the performance of AC units on NS.

 Chip I'm not 100% sure,but it's starts at around 1.8 percent to around 2 percent.I use to have a track chart which I can't find,and no body seems to have either

 But I nearly hung up this morning with 105 empty aluminum hoppers and a two six axles in the rain trying to get up the hill to spot up   

 I'll dig around and try to get more details to be more accurate.