I am using this library and love it. only con is the samples are large and eat up memory. I get around large orchestra works by writing the strings first, then freezing the CS tracks before adding in the rest of the ensemble. 

As for performance issues, as you mentioned Alex emailed patches that cured my issues. He mentioned they were going to be releasing a public update at some point to correct these as well. They are very customer driven, that is impressive and rare.

Personally I think the library is amazing and produces some terrific realistic results. I highly recommend this product.