Ted,
The following link:
http://www.cisco.com/en/US/products/hw/contnetw/ps792/prod_bulletin09186a008017dc5d.html
states that "A Cisco CSS 11506 can now achieve more than 45,000 TCP connections per second and, if configured with 4 SSL modules, can attain over 4000 SSL transactions per second."
Is that what you are looking for?
Keep in mind that performance will be slower with layer 5 rules than strictly layet 4 rules.
-Steve