My MRP is nice- light, strong, well made, easy to set up My old Superstar one was semi-decent but the cage was a little brittle, and the backplate really a bit too flexy. And it was a bollocks to set up without rubbing, I think the cage just isn’t quite the right shape. But it did the job
I’m not using any guides now though- thick/thin rings are ime more reliable than chainguides on standard rings, and much better when they do fail (since chains can jam in chainguides and always take longer to remount, whereas with a thick/thin it’s the work of seconds to sort). Thick/thin + chain device may very well be better still but I don’t feel I need it- and it strikes me that there’s a whole extra world of chain-refitting bollocksness there to be visited.