Having the expansion pack is a real bonus. It allows improved graphics on some games and some of the more advanced games will not run without it. The games are cart based so no worries about scratched discs. Games canbe found cheaply on listia, 2nd hand/thrift stores, etc. The connectors on the game carts can be cleaned with a qtip and rubbing alcohol. Just be sure to let it dry before trying the game. Some games support up to 4 players with the 4 built in ports. Some simultaneously in 4 player split screen. WOW. I have had mine for several years and am happy with it. Would bid on this one but already have enough spares. (When you have collected as many games as I have spare systems are a must) hope this info helps