I love these blanket statements based on personal anecdotes.
My equally valid blanket statement: Both of my 4TB FW800 G-Tech G-RAID drives mount and function perfectly. I'd upgrade to Mavericks immediately!
Reality: I'd do what I really did months ago testing the DPs. 1. Install Mavericks on a separate drive. 2. Test. 3. If satisfied, make a fresh clone of my existing system in addition to my normal TM backup and existing biweekly system clone. 4. Install Mavericks on my main drive. 5. Test. 6. If satisfied, continue. If dissatisfied restore from the clone and try again in 3 months.