My guess is that you would be happier w/ OME & OME. They are designed to work together. Shock length will be correct.
I can not tell you the difference between 5100 and OME shocks because I only ran the 5100s w/ OME med coils. I ran that set up because I had the 5100s already and picked up the OME springs cheap. Ride was stiff and terrible in any sort of whoop, pogo-stick effect.
I can tell you that the shocks were too long and quickly wore out my upper ball joints. If you do use 5100s and OME I highly recommend aftermarket UCAs.
:cheers: