I think there is no problem with the list.
Omer is basically trying to compare the best engine out of the ones he has listed.

If I were to arrange the engines OUT OF THE ONES LISTED BY OMER ...

i would arragne :

OS 61 FSR
MDS 68
YS 63
Magnum 61 XL ..

so we must try to judge the best engine out this particular list of engines. !