Reply to Ipad GB size?

I am getting a IPad 2, but not sure what gigabit i should get. I am a producer, and will be using both apps Touchable and Launchkey A LOT. I am not looking to spend my money on gigs I will not use. I have about 1,000 songs and gaining more rapidly, i don't use that many other apps, maybe about 5 other ones. Help me out?