I have a customer that wants to upgrade their PIX 515. They already have upgraded the onboard memory but not sure why since their net admin just left the company before completing the upgrade. They want to finish the upgrade of the OS from 6.3(1) to a newer version but they are not sure what they were upgrading for.
Whats the highest recommended stable upgrade for the 515? Stick in same major version up to 6.3(5) or would it be ok to jump to major versions like 7.2(1)