I have an RSP Plummet, a couple of Reverbs and a Joplin.
The Reverbs are great and have only ever needed one service between them (they must be about two and three years old).
The Joplin is unreliable, wobbly and currently needs hoiking up with my thighs because it won’t return on it’s own.
The RSP is a bit agricultural but works fine. I got it off a mate who had problems with it sticking after mucky rides. He took it apart to service it but then couldn’t get it back together and gave up on it. I stripped it, regreased it and added a ziptie to the top of the rubber boot and it’s been 100% reliable ever since (cue catastrophic failure on next ride).