The rebuild's are not anyones preference. The engines themselves are fine, but the way they handle is very squirrelly, especially MU'ed. Over the past few years they have been matched with relatively decent counterparts. You'll see 91/97, 93/92, 95/96, 94/99, 90/98 paired off more often than not.
I was fortunate to work the 2013 season when the 100 was still around and it was assigned the Carcross train. Didn't have the decades of prior experience some of my older UTU coworkers had but they were sad to see them get converted. The smoke was reduced which is a plus for passengers, but the rebuilt engines act nothing like the old ones.
That being said, I'll miss some of the 101's that went to Durango, particularly the 103. That was a fun engine to run. It replaced the 100 on the Carcross train mostly since 2015.
John Hillier