Should I return my 16g S4 for a 32g?

I've recently upgraded to a Samsung Galaxy S4. I initially ordered the 16G version over the 32G trying to save a few dollars. But, now I find that I may of wanted that extra 16Gs just for the simple fact that I want to get the most out of my upgrade (considering I can only upgrade every two years) and also, with my previous phone, I only had 8Gs of memory (iphone 4, which couldn't be expanded) and I found that to be too little (I hear that the 16G S4 has essentially 8 or 9Gs because the OS takes up much of the storage).

Now, I've heard that you can buy an SD card and upgrade the 16g S4's memory, but I'm not sure if that'll solve all the problems (As I heard that there are some apps and such that can't be saved via an SD Card)

So my question is, should I go through the trouble of trying to switch my 16g phone for a 32g (I would have to return the 16G and pay a restock fee, etc)? Or should I just stick with the 16g and buy an SD card should I need anymore memory? Also, does the 32G perform better than the 16G? (I would assume not, since the only difference is the memory, but it never hurts to ask)

But all your pics and music will go on your sd card.

I'd keep the 16g and just get an SD card. A 32g SD card is not too expensive and should provide you with plenty of memory for music, pictures, and even some movies. The card might even be cheaper than the restock fee. The 32g model will not be any faster/better than the 16g version.