I'm using stock belt from the day I got TA05, which is almost a year now. I'm using 3in on rear, 4in on front right now. For the whole lifetime of my TA05, I didn't have sngle belt problem somehow. Maybe just lucky, but I still install FK04 belt tensioner on rear recently just in case.
I put 0.7mm shim between bearing holder and CF plate. You might need to use different shim to fit your belt best.