Is the iPhone 3GS still worth it?

Using a Wildfire S here, driving me mad. Problems with storage and lag are making me consider buying an iPhone 3GS second-hand off of eBay.

But as the title says, is it worth switching? I don't mind sacrificing the 5MP camera in favor of the 3MP one as I rarely use the camera on my phone.

Added (1). Obviously, I can only afford a 3GS.

Yeah still a really good phone, you can actually get 3GS free with a 2 year plan now on many carriers, hard to beat that price.