If you don't have 100% identical spec to what the chip has been written for, like a larger comp wheel then the chip will be no good.
The trouble with pf is you will only hear the good bits as people don't have the balls to slag off when it is deserved, there is no company in the world that has never cocked up, it's human nature, it's what they do about the cock up that shows what they're like imo.
Either mentioned will do a good job generally, so long as they have a matching spec chip.
A mapping session on your car will be the best though but cost more it can really make a huge difference to get the best.
tabetha