I want to find out on a mh rod for plastics and jigs do you prefer a fast or extra fast and why.

The terms are relative and have no specific definition or standard, but the lighter the bite, the faster action I like.

for medium to lighter cover, i like fast for heavier cover i like XF.

 

mitch

I like XF for most of how I fish (soft plastics)...

Either will work just fine for plastics. I use both without issue. 

Go check out the rods you are looking at buying in person. They actions vary a lot from brand to brand. A medium heavy fast tipped rod can feel totally different from two different manufacturers.