@Noel, do it. Season 2 is great, season 3 is awesome.
I've already seen all three seasons or series of this show and reviewed them in the anime reviewing thread. The first series was decent, as it didn't really know where to stand as a show. It felt like it wanted to be a serious, mecha-combat driven anime series. However, there is too much comedy/romantic humor in it that it makes the show feel out of place at times. Plus, the mecha combat can be very boring and just a let-down as whole. Though, the music in the openings is great and art is really good by Kyoanimation for Fumoffu and The Second Raid, since it's one of the studio's first series project. (Gonzo art for 1st season is kinda bleh at best)
The humor gets better as the show goes on though, and I love how that Tessa girl is an American and she gets to be captain of her own secret submarine at only age 16. Fumoffu is one of the funniest slap-stick animated comedy series that I've ever seen. Literally, the humor never gets old in the show. The Second Raid, however, is more action based and kinda feels like 1 big, 6-hour long film that doesn't have a proper ending. Which sucks, because the anime was great until the ending happened, which was rushed and should been handled better by Kyoani.
Unfortunately, you have to read the manga/light novels to finish the story as we're probably not getting season 4 ever or anytime in the near future. TSR ended in 2005, I doubt the creators of FMP really care about giving their licenses to studios for them to finish animating the show well after TSR ended. The lack of a fourth season hurts this show due to some plotholes and things unexplained in TSR.
Oh and DEFINITELY watch the show dubbed. While both versions are good, the dub makes the show a whole lot funnier and just better IMO. Overall, they are three really good anime series. But there are plenty of shows out there that are much better. (Like Code Geass or FullMetal Alchemist)