YES, another oil question...sorry... but I have been searching around the many existing oil threads and can't seem to find my answer. I have a 2010 Versys with almost 18,000kms on it (about 11,000 miles). I have been using OEM filters and oil. My question isn't if synthetic is better, but...

I switched from whatever oil the guy who owned my V before me used to AmsOil 10w40 full synthetic about 1,000 miles ago. Is it time to change it again because of the change of brands? How often should it be change hereafter? Is there an oil filter that's vastly superior to the Kawi filter?