a moki/rcs 1.80 will easily pull unlimited vertical on a 15lb plane .
a mvvs 1.60 will pull tall verticals on a 15 lb plane. since your plane is only 10 lbs there is no need of putting too large an engine.

putting a big engine will be heavy .... then you have the CG to deal with. doing manoeuvres with too large an engine means generating more speed/torque which means you need stronger frame/body to deal with the engine.

the rcs 1.40 gas is a good engine and can hover upto a 12 lb plane if i remember correctly. will run 16 inch props in the 8000 rpm range.
the mvvs 1.60 will generate more thrust and run upto 18 inch props at 7000+ rpms.

check these forums itself for more info on the engines you have mentioned.