Didn't enjoy the series when I first, but I tried it again after I bought FE9 due to Ike's reveal on the Dojo. And holy crap was FE9 a good game. After beating it I tired the other US releases, which I don't think were as good, but they got me to keep an eye on future releases.
Started importing the series after I began taking Japanese classes and learned how easy it was to import and play games on older systems. FE was just a given since most games don't need a knowledge of Japanese to enjoy, and translations could be easily found on Serenes Forest. FE3 is now my second favorite in the series.
Beyond that I enjoyed that the series didn't have a weird fanbase, falls into a lot of TV/Anime tropes, use fanservice in anyway (at least until FE13 >_>), that the art style held a lot of charm/was bright and colorful/reflected what was in-game, and character portraits having animations during cutscenes. The characters and world within the games also felt a lot more realistic, fleshed out, and has never really been over the top. And yes, I'm comparing a lot of this to FF & DQ.
Shadow Dragon's good, just don't expect it to wow you. The story is pretty barebones compared to other games, no support conversations, and to access extra characters/chapters you need to kill off your army.