I've (as a med student) worked with a psychiatrist, FP, and GI-doc who used practice fusion. (Colorado and Minnesota)
It's a decent enough system. Easy to use. You gotta go back at your notes and look up what you diagnosed the patient with. I don't think there's a place where you can just see all the cumulative diagnoses nor h/o medications, if I recall correctly. The Practice fusion system does make the linking to labs and prescriptions e-sending easy once you learn the shortcuts like "tab" and also just entering "t" when you want to choose "tablets." An annoying this is that the system will let you send controlled substances through, but the pharmacist just gets something useless that they can't fill and they aren't sure where it came from or something. So you just have to remember to write out the controlled substances ones. There is this nifty Rx printer you can hook up to the system that will print out in your office that you need special expensive paper for...which then you just sign and give to your patient, and have it all documented in the records. It is also really annoying to have to check off on all the "contraindications."
My FP could get through charting while in the patient room. He'd just put the billing level code at the end of the "P" for ease of billing.
My psychiatrist was a bit computer illiterate, so it was more challenging. With the general template just "S" "O" 'A" "P" though, it kinda flowed into how my doc was used to writing. As a one person private practice, she could use the scheduling function without any issues. For anyone in a group practice, I think they have a new-ish function where you can see everyone's schedule on one calendar...but I"m not sure. There wasn't an ability to just make a set of pre-set checkboxes to check-off on signs/sx which then would populate a nice sentence unfortunately...so it definitely isn't a nice fancy Epic EMR system.
The scanning files in thing is also pretty easy and signing off and assigning files to patients is also pretty simple to do.
Cons: when a winter storm takes out your internet....you don't have access to your charts cuz there isn't an ability to auto-store a backup in your own facility. =(
Customer Service: When I set up my own experimental practice fusion thing, they actually had someone call me to make sure I was doing alright with it. So it seemed pretty responsive.