I don't know if this helps but...
Late 2011 hires antiglare 15 in MBP, 8 GB RAM, 7200 RPM drive, i7 2.5 Ghz.
Under 10.7.5 it Geekbench 2'ed at 10,500. Under 10.8.3, it hit 9300. Under 10.9.2, it hit 9700. Do I need to get back to 10500? Not so much. I just need the thing to be ready to do what I need when I need it.
For a while after installing Mavericks over 10.8.3, I was seeing beachballs galore and I was pretty frustrated. I was routinely submitting snide remarks about "rolling back to Snow Leopard" with every mail.app and airmail.app crash report I submitted to Apple. There were a few steps I took to banish the beachballs (hopefully) once and for all...
1) SSD - I picked up a Samsung EVO 840 .75 TB SSD
2) Fresh Install - connected the SSD via a USB to SATA cable, installed Mavericks from a homemade USB stick and "migrated" from the Mavericks install that was still sitting inside my MBP then allowed Mavs to update itself to 10.9.2 before swapping the SSD into my MBP.
3) Archived 140,000 of my 160,000 email threads. This was causing Mail.app and Airmail.app to go ballistic upon load. Now that all those 4+ year old messages are archived, I can use email as a tool not an obstacle.
Of course YMMV but I find Mavericks to be stable enough for my use right now. There are a handful of things I believe Mavericks does better than Mountain Lion:
1) Memory management - I believe my 8GB "feels like" 12 GB when I'm running Mavericks. I noticed this before the 3 steps above and this continues to hold true after the upgrade to SSD/downsizing email hoard.
2) Automatic app updates - I don't remember if this was available in ML, but I definitely want automatic app updates on OSX as much as I wanted it on iOS. Frankly, it's something we should have had all along.
3) Notes aren't part of mail.app. I think this was introduced before Mavericks but to all those crowing about going all the way back to SL, it really was awful to have to launch mail.app just to take a look at some quick notes I took on my iPad or iPhone.
4) Kill Switch - I ran into this when I upgraded my HDD. If you boot from the recovery partition, it asks for your AppleID before you can do anything. This doesn't quite qualify as a kill switch for stolen Macs but it's a step in the right direction. At our company we have thousands of Dell and HP notebooks. We only have a few dozen Macbooks. 6 of them were stolen a while back and it would have been nice to have the ability to use "find my Macbook" to recover them more quickly. The cops finally did find the guys but we haven't gotten our computers back as they are evidence in the trial.
I should also mention I have Mavericks running on a 2010 Mac mini. There are a few more beachballs but again a fresh install to SSD makes for a smooth running system. The configuration is similar to my MBP. There is 8 GB of RAM and a 500 GB Samsung EVO 840. Putting the SSD into the Mac mini was a 46 step process (detailed on
iFixit) but it was well worth it.
On both systems, I used Chameleon to enable TRIM support. On both systems the drives are less than 60% full and huge files are kept on either firewire, USB or NAS drives.
Hope this helps...