While no show, including B5, is perfect, I think B5 came closer to capturing the "essence" of a good sci-fi book than any series ever has. The idea of having a story arc (beginning, middle, end) such as B5 had is an unusual one for an American series, but it made this show highly effective. Its storyline developing over a five-year stretch, B5 actually can be broken into 3 "segments"; the "bookend" seasons 1 and 5, in which characters are introduced in the former and the aftermath of the main story line is cleaned up in the latter, while seasons 2, 3 and 4 serve as the "meat" of the show. It is really in those seasons that the show hit its stride, but it wouldn't have been as complete of a series if it had not had seasons 1 and 5 the way they were.
There are some negatives -- the show has a penchant for throwing in some gratuitous (and generally poorly directed) fight scenes (in a manner similar to "The Prisoner"), and its humor can also be a little too "yuck-yuck" at times. All in all though, this series is for intelligent viewers of TV, regardless of whether you consider yourself a hard-core science-fiction fan or not. It also deserved better treatment than its Season 5 patron, TNT, gave it and its aborted follow-up, "Crusade."
There are some negatives -- the show has a penchant for throwing in some gratuitous (and generally poorly directed) fight scenes (in a manner similar to "The Prisoner"), and its humor can also be a little too "yuck-yuck" at times. All in all though, this series is for intelligent viewers of TV, regardless of whether you consider yourself a hard-core science-fiction fan or not. It also deserved better treatment than its Season 5 patron, TNT, gave it and its aborted follow-up, "Crusade."