I bought a new style 500 last year and like the shape of the old round style better but the function is as good and probably a little better. Have not fished it too much yet but the drags seem a little better as well.
Good stuff from the few that I have done. They made improvements to the side plate to make the ARB more accessible and also have placed seals on the front and back side to improve resistance to water intrusion. Drags are now carbon fiber.
It is a bit more fiddly to service. I like the addition of the side plate to seal off the spool. Handle seems nicer...we'll see how it holds up over time.
Line counter still sucks (maybe more so) both the mechanism itself and window. Still has plastic idle gears.
I believe all modern level wind reels have plastic idler gears. This is done so that in case you get your finger stuck in the level wind when a fish is running, the plastic will break instead of your finger. IMHO the new Tektas are superior to the originals but you're right: The counter sill sucks big time.