Yes, I have two MKS 5mm tensioners on my Pista, and I can hardly see them.

They work great.

I have two MKS 8mm tensioners on my Surly Karate Monkey.

When and if you intall MKS tensioners, the flat washer portion goes between the hub and the dropouts, and the MKS logo on the tensioner barrels goes outboard, away from the center of the bike; outboard left on the left tensioner and outboard right on the right tensioner.

Start out with a chain a little too long, and shorten it a link if necessary.

With a little experimentation, you can get the hex nut inside the barrel flush with the barrel.
Experiment, and start with a chain one link too long.