I have a outdoor power equipment business and use a lot of belts, try to use oem if possible but also use aftermarket as well and in some cases are better than oem, saying that I know that there are 2 primary manufacturers for most belts out there, gates and Carlisle. I run cat's a 2007 f-1000 and a 2017 eltigre 8000 2 stroke. F-1000 needs belt and looking for spare for 2017, I have heard in past that some aftermarket compounds can be too hard, I also understand that oem is always best but would argue not always best and sometimes aftermarket exactly the same as oem. Having said that I have access to gates belts and was wondering if anyone has any input on good or bad about them.