I'm getting a EX-Flash cartridge as a gift for some who has both a DS Lite and a GBA and reading the description of both the 3 in 1 and IV they both can handle being played in both systems. I also have an R4 with Wood R4 installed with 2 GB capacity on the DS. My questions are as followed: How does the 3 in 1 get games on it if's it GBA compatible? Do both come with internal batteries that I might have to change? Are both of these compatible with the Wood firmware so you don't have to take it out in order to play it? Which one is the most compatible for GBA games(M&L Superstars, PKM, etc.) and gives me the most bang for my buck?