I've used a 64gb 3G model for almost a year now.  I am currently on my iPad 2 and will never go back.  The speed is very noticeable.  My vote would be to spend the extra $$$ and get a 16gb 3G model.  Unless you don't plan to use GPS / 3G.  Home share with iTunes is working well so I no longer have the need to store most of my videos.  The iPad 2 is crazy smooth.  I highly suggest trying it out.  With all of that said, I loved my first iPad and could have easily kept using it without regret.