I had Camworks and switched to HSMWorks and couldn't be happier.
Support is excellent - probably the best supported piece of software I've purchased. You can probably assess their support by asking them the question about the tool library on their forum or through their support channel.
I can't comment on Solidcam as I have no experience with it.
I use Solidworks service pack 4, HSMWorks 2.24280, and Windows 7 Ultimate all in 64-bit. It runs very quickly, but I have a fast PC (Gulftown processor, Crossfire ATI cards, SSD, 12GB RAM).