I'm a big fan of SunTour Cyclone GT RDs, already had a couple of mk2s then my latest project really needed 37 chain wrap.
So I got my first Cyclone GT mk1, and I really like it.

Mk2 possibly works slightly better, but almost impossible to tell, they're both great.
Which one looks best is a toss up - i always polish the printed logo off the mk2 so it's just shiny and very very small.

There's a mk1 GT on Ebay UK for £35 atm.