Bushnell put "ERS" on the box of my ET6245FG, which may cause some confusion when we're talking about different Bushy scopes online. But most generally, when someone's talking about the ERS scope, they're referencing the 34mm 3.5-21x50s with 10 mil locking turrets/zero stop. AFAIK, they don't make a 30mm tube 6-24x50 w/locking turrets & zero stop.
Whatever - I bought one of the ET6245FGs after having shot my 34mm 3.5-21x50GZA for a couple of months - mostly wanted to see how the optical quality compares to the 34mm model. It's not bad - I rate it brighter than either Vortex PST 6-24x50 or Sightron SIII 6-24x50, and it tracks well. The turrets are free-wheeling once you've loosened the cap screw, so there's no problem getting the turret marks to align when you're zeroing. Clicks are distinct & audible. Only issue I've had with mine is that I've had a tough time getting ocular & parallax focused for a sharp image from 600yds on out. Don't have this issue with the 34mm 3.5-21x50, but at my age (62), it could be due to vision issues on any given day. IOW, some days I don't see worth crap. I'd want to test several examples of this model before condemning the optical quality, but generally speaking - even though this scope's image is brighter than my PSTs or SIIIs, it's easier for me to adjust the Vortex or Sightron for a sharper image at 24x.