I periodically return to enjoy the Roswell TV series since first watching it in 1999. (In fact I bought this disk set again after one of the disks in my original set, bought many years ago, was damaged.)
Roswell has the sweetest romance I think I've ever seen in a TV series. Shiri Appleby and Jason Behr do an amazing job as the lead characters, pulling viewers into their emotional story. Jason Katims wrote many of the episodes, and directed many of them. He also conceived the series, after reading the first book in Melinda Metz's series of "Roswell High" young adult novels. Jason Katims' steering of the series is what makes it so remarkable. Here we have something that has a science fiction (SF) premise, but is about people's emotions and interactions -- something quite rare in SF. That's because what Jason Katims does best is writing about human drama. (He'd previously created "My So-Called Life".)
The first season of Roswell is the best season overall, in my opinion, however some of my favorite episodes are in the later two seasons. During its original screening the show developed a remarkably devoted audience all around the world. This following remains devoted to it all these years later, with websites and surprisingly high quality fiction continuing to be written by fans of the show, filling gaps in the series and extending it.
In my experience people either love Roswell or they have absolutely no time for it. If you're one of those people lucky enough to be deeply affected by it then you will return to it year after year, probably for the rest of your life, to have your heart nourished and re-infused with hope and romance. It has left an indelible mark on those of us privileged to be affected by it.