Vixen SXP2 PPEC and VPEC?

[900SL]

I've been considering a SXP2 for a few months now. Ticks a lot of boxes for my particular circumstances, decent quality, belt drive, solid mount.

I'd love to hear from anybody who has one and whether they use the PPEC or VPEC, which I understand is preset PEC and built in at the factory (presumably accessed via the SB10) 

There are quoted figures of +/- 4 arc seconds out there peak to peak over the worm cycle using the PEC capabilities which would suit my wide angle imaging up to 200mm looking at pixel scales. Is this a correct assumption?

Does it actually work in practice, with (I assume) a gradual ramp on PE resulting in sharp stars on shortish exposures when unguided?

Does PPEC 'play along' with a separate autoguiding and dithering set up such as ASIAirPro for longer focal lengths?

Many thanks for any feedback..