As many of you know, I actually watch Sliders very regularly, an episode every week or so. I kinda bounce around on the episodes though... But recently (basically 2015) I've been watching a lot of original cast episodes, keeping up with SlidersCast and started with the Sliders Rewatch. I always defend seasons 3.5 to the end, because even though the original cast is not in tact, there are some good episodes, great ideas, and a lot of great scenes, even with the "new" sliding teams. Just the other day, however, I watched Way Out West (which I claim as my second favorite episode of the series), and going from watching most of season 1-3.5 episodes to that was almost a shock. It was still enjoyable, but something was missing.
I've probably hammered this sentiment into the ground. But the inescapable truth is that when you follow a TV show regularly, you are letting specific people and faces into your home. If those faces suddenly change, it's akin to a home invasion. I didn't invite Maggie over for dinner; I invited the Professor. Who does she think she is?
There's also the fact that in Seasons 1 - 2, all the characters were from 'our' world. Therefore, they could compare our history with alternate histories and react accordingly. But with Season 4, Quinn and Rembrandt are from an Earth that was invaded by Kromaggs; Colin's from a pre-industrial Earth, Maggie's from the Pulsar world where nuclear weapons were detonated on American soil -- there's no sense of contrasting our world with this week's world. None of these characters are from our world, which makes it impossible to create the homesickness and alienation that were so prominent in Seasons 1 - 2. The show became absolutely pointless.
That's probably why I'm not overly in favour of a sequel series where sliding has existed since 1995. I'd rather see Quinn discover it today. And see him played by Gregory Smith.