i run Graphtecs all day long.. 8600-130's and 30' plotters as well and i run a 45 degree blade all day long on cast vinyl, calendared vinyl, vinyl paint mask & printed & laminated contour cut graphics.... I get years out of a Graphtec 45 blade.... If im cutting reflective a lot, ill swap out another dedicated 45 degree blade but i never use a 60 blade... I even cut this small on my plotters...
The 30 for reflective isn't your typical reflective. They're talking about road reflective.... Such as diamond EGP/HI/DG - the ones with a hard shell and prismatic beads. While you can use a 45 with it... It'll likely snap the blade, or dull it really fast. For those you need a k30 blade that's made out of a different stronger steel.
60 degree is meant for super thin stuff like window tint and really small letters. You don't seem to have an issue cutting small stuff on a 45 degree blade! You should give the 60 a try if you.do that a lot though... It does give it a more.consistant cut, which makes weeding easier (small letters are always a pain).
And just a note - summa and graphtec do things differently... For the graphtec a 30 is for thick, 45 is for regular, and 60 is for really small thin stuff. On summa it goes 60/45/36.... Complete reversal. So if someone's reading this and confused about the blade degrees.... Just know it's different for different echosystems!