It's not too late to try it. It's just never, ever, ever going to get any better than it already is. And when it stops working with OS X (who knows when that will be), they won't fix it.
Try it. If you prefer it for now, use it. Just know that eventually you won't be able to anymore.
And yeah, I wouldn't pay either. This one be the one instance where I wouldn't argue with piracy; they've abandoned us because Google made them rich. They stopped development on Sparrow, and wouldn't even open up the source code so other people could continue development. They just kept charging (without even a price reduction) for a dead product.