My current ROTJ helmet is from RS. I'm far from an expert regarding helmets but I've been happy so far with my purchase.
I've done around 30 events over the last year with it, and it's held up great. Even survived some knucklehead smacking me in the back of the helmet hard enough to nearly knock it off my head. The aluminum hollow stalk is nice if you want to upgrade to a light kit for the rangefinder too. No dental files for the back of the helmet are included, but it's easy to get 3D printed ones and add them yourself. Visor is epoxied in place, which isn't my favorite way for a visor install, but it's held up to Blast a Trooper well enough. Basically put, it's a pretty solid helmet so far, after a year or so of use.
Paint job is alright, I think Simon does a lot of their paint ups and for the number of helmets they put out it's decent enough. If you want ultra fine detail going with one of the painters here on TDH might be more down your alley. The cheeks on mine were totally black, and I think most color references are a black/green mix, so there's that to think of as well. There's no physical damage to helmet as well, so if you want something along those lines you'd need to add that.
Looking at their website, they do list both the kits and finished helmets out of stock. I know for certain props they're pretty backed up, and the time from purchase to receiving your helmet might be a long one. If you like the idea of having your helmet molded and painted by the same place, and you're in no hurry I think they're a good option. That being said, there's some equally great vendors here on TDH too that might be a little quicker if you'd like your helmet sooner.
I love my ANH Stormtrooper from RS and the helmet has been great for me. YMMV.
I'm awful with a camera so I'll skip posting pictures for now, as it'd probably not do anyone any favors.
