go with the Galaxy S, I own one right now and a Cowon J3.
I have to say that the J3 is better because of the equalizer and all that fancy BBE/ViVA stuff. But the SGS with voodoo kernal + voodoo sound is much better than Ipod/ipod touch (without equalizer app) (haven't tried with equalizer since I have a J3).
If you dont know how to flash phones and root android devices than it could take some time reading up on the SGS on the forums.
PS. The SGS has many flaws for a phone though, it requires fixes for GPS/Speed etc. Unless you're in a region that has the latest official froyo update 2.2.1 than you need to know how to flash custom roms to make the phone usable.
I used to joke how the phone was going to get me killed one day because sometimes it would take over a minute to load the app to make calls, which would be bad in an emergency
EDIT::::::
I want to clarify, I own the Samsung Galaxy S GT-i9000 16gb. It is the Europe/Asian model of the phone. It is unlocked and non-carrier specific.
There are many versions of the SGS that are carrier specific, IE: Captivate, Fascinate, Epic4G, Vibrant, and maybe some others I haven't heard of.
Please take some time to read this link about more information about the different versions of the SGS
http://www.phonearena.com/news/US-carrier-versions-of-the-Samsung-Galaxy-S-explained_id12223
Reasons NOT to buy this phone:
1) SGS2 is coming out end of march
2) You NEED to be technologically inclined to make this phone good.
I DO NOT RECOMMEND DOING ANYTHING WITH YOUR PHONE IF YOU ARE NOT TECHNOLOGICALLY INCLINED. BECAUSE IT COULD BRICK YOUR PHONE.
Please be very careful if you decide to do anything with your phone like Rooting or flashing custom roms because it voids your warranty
Sorry if there was any confusion with my earlier post