The lap bars are also a little wider, because the outside is flat, not a tube. I tried it and I find them to be very comfortable. Then again, I never had a problem with them in the first place, and I like them better than the PTC's.
Regarding which trains are used, that's entirely up to the customer. The customer can have Gerstlauer or PTC, it's their choice. I don't think CCI cares either way. The Gerstlauers apparently are a little less expensive.