It depends.  Both have their plusses and minuses.  The GS has a bunch of stuff built in that the IIe doesn't (serial card, floppy cards, faster CPU).  The IIe has a built-in keyboard and (according to me) more retro cred.  In terms of pure monetary value, it's probably not a good deal for you, if that's important.  If you do go through with it... be sure to get a keyboard and maybe a mouse to go with it.