Originally Posted by veganbikes

Either will work 7 speed stuff is quite old school and if it is more modern I would be careful putting money towards it as the 7 speed era was in the late 80s early 90s.

Originally Posted by soyabean

The reason why new Tourneys work so well for 6s/7s is because of better modern manufacturing that was more difficult 25 years ago.

I've installed new $5 Sunrace RD's that worked flawllessly.

6s/7s bikes aren't serious and Tourney is fine.

I would recommend a premium RD where is is required and noticable, 8s and up.

Originally Posted by Bill Kapaun

If you're a casual rider, even a Tourney level would suffice.

The thing NOT to do is 'upgrade" too much.
As you increase the number of speeds, the cage etc. gets slightly narrower each step, making things more finicky when there is no need.
Keep it to a 7/8 speed max.