The collection to beat all collections!
There are 28 default games in SGC and almost all of them are instant classics. The Golden Axe games give a great chance to play some classic beat um ups with your friends and then if you want to reminisce on the old platforming games, you can switch to Ristar or the Sonic the Hedgehog games at any time. One of the great things about this collection is that unlike the original games, you can save your place at any time so you can switch around games as much as you like without having to worry about your lost data. You may also find some games that are truly amazing that you've never played before. I had never played Gain Ground before this collection and I now see how amazing it really is. While the graphics are obviously lacking, my friend and I had as much fun playing the 2 player co-op as we would have playing any of the current gen games! Also, if you like to unlock bonus features in games, this one won't leave you lacking. There are plenty of developer interviews, museum facts, other videos and even 5 Sega arcade games that you can play. There is definitely a lot to do.
The sound quality in the Sega Genesis Collection is a perfect match to the original games without feeling like a simple emulation. Some of the songs you will remember forever like the Green Hill theme from Sonic the Hedgehog.
One of the great things you will see in this collection, as well, is that graphics truly don't make a great game. While most of the games had incredible graphics for the time, none of them stand up even close to today's games but that's not why the games are great! The gameplay is what truly matters and it shines through in every one of these great games.
Basically, no matter what kind of game you are looking for, the Sega Genesis Collection will have something for you. I highly recommend it to anyone whether you had the original Genesis or not.