ST2, even as it is right now, is an excellent coding tool and IMO certainly worth the purchase price. It has more than paid for itself in the conveniences it offers. Even if it never gets updated, I am happy to have bought it.
There’s also an active plugin community. I don’t see why an app needs to be update often to be considered worthwhile. I use ST2 every day, almost all day. There are no problems I run into, and (especially thanks to plugins and snippets) no shortage of features that leave me wanting.
YMMV, but I have found it to be a worthwhile purchase.