MP3 files by default are not gapless. Players have to be specifically programmed to remove that gap by loading and playing the next song early, which is why almost all players still have gaps (though why companies don't try for gapless I don't understand.)
For ripping MP3s, I use CDex with the latest LAME drivers (though some version or other is already included.) Don't use anything besides LAME. For good quality, I'd rip at VBR between the lowest you'd like to listen to and the highest you want to go to save space.
Anyway, I have a shuffle and I love it. You won't like it if you listen only to full albums and want to fill it up with them, if you want to select a specific song that you didn't already place in a certain position in the list when the shuffle's connected to the computer, or you need to see what song's playing (I don't miss this feature but I know most of my library.) You also have to like listening to random music obviously, as that's its main feature.
Things I like about it are the sound quality (best I've heard in an mp3 player, though people who like EQing are out of luck), simple controls (I can put it in a pocket or under my shirt and control it through my clothes), iTunes compatibility (you have to try the program to see what I'm talking about, especially regarding smart playlists), cheap price, and easy access shuffling (just slide the switch on the back.) Battery life's great too at about 15 hours or so, making it an Apple first, underestimating battery life. If your idea of using a portable player is putting 3-5 CDs on and autofilling the rest based on you choice of music (using smart playlists) to listen to randomly, then it's perfect. You can get to about three CDs from the beginning or go 2 CDs backwards to the end of the playlist quite quickly just pressing next or back a bunch of times, though any further and it becomes a bother. If any of its drawbacks bother you then don't even consider it, but it's a great player for anyone else. Everyone has good things to say about the Creative MuVo series, so take a look at that.
[edit] Beaten to the gapless playback thing.