I have some jam points I can use towards an IK product.  I'd have to contribute some cash.  Is the upgrade worth it?

Excellent library, can't go wrong with it.

I have it since it came out. To my ears, it is really designed for mainly classical music. Any of the pop, rock, jazz, country, etc, projects I have tried using it on just did not work out very well. But it is priceless when it comes to the traditional classical tones! Just an opinion. I had the same opinion with original Vitous collection.

The piano is really nice

I use MP2 often, but it's very different than your typical orchestral library from Spitfire or East West. Since it sounds as if you're upgrading you understand the differences and there is then no doubt in my opinion that MP2 is better than MP1 and worthwhile.