Well, I don't use OC, I don't use FasterN9, and still I find the performace good all the time regardless of uptimes...
(well it's only 7 days now because I did some boot stuff back then... but generally I only boot my device when I need to change to different kernel/OS...)

I do not think you need to boot your devices regularily to have good performance. If that's required, then you have misbehaving applications or you have yourself done some tuning of the device that has turned sour.