I live near Pittsburgh PA, so am familiar with a few trainers out this way.
I own a gelding that Jason Prince (exponies above) owned and trained, and the horse is the most versatile in my barn, not a hole in his training. Jason has been wonderful to deal with, even years after I bought the horse from him.
I sent a horse out to Bill Eperthener at E pony last season, and again, not a hole in the training, and very happy with the training. Both Bill and Frannie are excellent. They do both driving and halter, but Bill is "famous" for driving horses,
I have a horse out with Arlene Foulk at Foulks Fantasy Farm this year and Ive been very happy with Arlene too.
Generally, where I send a horse depends on if I also want to show that horse Ammy along with the trainer showing it (if so, the trainer needs to attend shows in an area I can also reasonably travel to) . If Im planning to show certain shows for the season, I try to pick a trainer who has those shows on their list, to cut down my traveling (if I'll already be there with other horses, it works out great for me) I would send any of my horses to any of the above trainers in a heartbeat, and trust them with the care and training of my boys.