Should I upgrade 4.5 year old macbook pro from Mountain Lion to Mavericks?

[iMore Question]

I'm confused about when/what I should upgrade my 4.5 year old MBP to. It's currently on Mountain Lion. I've avoided Mavericks due to poor reviews I've read. (My MBP runs incredibly slow, despite taking it to the Genius Bar for a "tune-up" which lasted about 2 weeks.) Yosemite is too new for me to feel comfortable jumping in yet. What's your advice about upgrading now to Mavericks while waiting for Yosemite to shake out? Do you think an upgrade will improve the MBP's performance?

Many thanks -
K. McGee

 

[Trees]

If you can share more details about your current system (CPU, RAM, Disk, etc.) that will help provide more clues as to what upgrade(s) may make sense.