While I don't own both, I have handled the Tispine a few times at Bladehq. The things that I did not prefer regarding the TiSpine versus the SR2 are:
1. The blade opening hole that is oval/rectangular doesn't allow for a fast opening. While this may not be a concern considering you had one previously, I prefer the thumbstuds on the SR2.
2. Personal Preference, but I always prefer a stainless steel lock interface to just titanium.
The nice thing about the TiSpine is that it's lighter, more compact than the Sr2.
So as you can tell I own and prefer the SR2, with that being said; the aluminum version TiSpine is due out later this year and I'll happily add that to the stables providing it has a stainless steel lock interface (which it has to have considering the Aluminum) and a lower price point.