A QM1 hook is a circle hook,and once they are in they dont come out!...a bait with a smaller hook will be sucked up with more confidence than a bigger hook..i use preston Reflo 0.17mm or 0.19mm h/length,these are about 8 and 9 lb bs,this set-up with a soft action rod will land carp up to high doubles...Cheers Gaz
Guru QM1's may share a lot of similarities with circle hooks, but I wouldn't call it them 'circle hooks' per se.
The closest matches are the Kamasan B420 (sedge) and Drennan Starpoint.
Out of the three patterns mentioned I'd opt for the B420's, as I've found Guru hooks to be very inconsistent re quality; point sharpness, sharp edges on the eyes, burred hook tips....
As for hook sizes, I match the hook to the bait - A size 14 B420 to a 6mm bait, a size 12 to a 8mm.