The p30+ is a great back. Bulletproof, small screen, kind of like looking at an old polaroid, but if you know your stuff you can shoot it without tethering.
The plus series backs last forever and are so well built.
The 1.3 crop bothers some people, other's it doesn't I personally don't notice as it's not really 1.3 it's like 1.26 where the older p45+ was like 1.16 or something like that so the difference isn't that drastic.
I would suggest going through a trusted dealer like Capture Intergration as they will stand behind the sale and check it all out before selling.
For the price it's a deal.
IMO
BC