Mega Backup

I have recently found a backup unit for the megadrive at my local games shop. The bloke there wants £90 for it, i was wondering if its worth that amount. Its fully boxed and looks to have never been used.

if it's a decent unit that's not a bad proce for it though

emulation's cool, but there's something intangibly cooler about the console expierence
Turn the thing on and take a look at how much memory the thing has. If it has 3 slots it should have 24MB (8MB apiece). If it has more than 3 slots it's kinda useless because apparently no 32MB games will run on a Genny copier for some odd reason. Anyways, so if it only has 8MB, it's a ripoff. If it has 24+MB I'd jump on it. If you want more info I'd reccommend looking at
could anybody recommen one that's working on genesis? i mean, what's the best one ever?