I am too, but after reading the thread about the upgrade, lots of people seemed to not think it was worth it (no major improvements). So I think I'll wait a while.
I had 4.3 but upgraded to 4.5 because of a glitch with the speaker after messages with sound. I like the 4.5 but I miss my 4.3 so I'd say stay with it if you're having no problems!
My $.02 too!
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