I recently switched from PFC to haltech, the car runs the best it ever has,
For me the benefits are no MAF is great, the PFC random cough thing is gone, boost intergration is nice, having a few extra IO points is handy for running others stuff you might add and full data logging for diagnosis
Of course the skills/ability/attention to detail of the tuner will have a big impact on how the car runs.
Boost control will work with your existing solenoid you'll just need wire it up to the haltech and I'd run the external MAP sensor regardless of your desired boost level,I don't really like running a vacuum line back I to the cab
If I was to do it again and wasn't going for flex fuel I'd still ditch the PFC.