The shop blades are usually grabbed from a pile of stuff nobody cares about, so they're dull, bent, or just wrong for the material. I did the same thing for a month and swore I was saving cash, but every cut took twice as long and came out rough. Once I switched to my own, the jobs felt almost too easy and I stopped redoing half my work. The $180 paid for itself by the third project when I only needed one pass instead of three. Now I treat my discs like tools, not supplies, and I never touch the shop's junk even if I forgot mine. That time you spent wrestling with bad blades is the real money, so buy your own and don't look back.