You didn't state which model you own so I looked it up. I've been flying the K Model for 23 years. Just getting my second engine installed (factory). I've flown the plane over 3500 hours. 20% of that time in the flight levels over the Rockies or headed east in the jet stream. All that to qualify my experience with the TSIO360MB engine. I'm assuming you have an LB engine.
Mags live a hard life tucked back there in the heat. Pressurization just add more heat. I've had three mag failures. I won't bore you with the details but I will share my experience with "overhaul/inspection" matters. Neither is option IMHO, is worth the money. If you need proof, secure a copy of the shop guidelines associated with each process. At best, it's a bench test under circumstances drastically different than the working environment of thin air and high temperatures. I had a "recently overhauled" mag fail at FL220 over the Rockies with the wife on board. Nearest airport-40 miles away. Nearest airport with a maintenance facility - twice that distance. Vacation interrupted/AOG expenses and inexperienced hands diving deep into the bowels of my bird. Take away, never again as that was the third time I had experienced mag failure on so-called "recently overhauled" mags (under 150 hours).
My practice these days....mags come off the plane at 500 hours (period). I bought new mags (yes "new"). I paid the core charge and kept the old mags. I have my mag shop replace everything in the case (yes, even the coil). The backup mags are in the hangar ready for the next swap. No issues since then and believe me I'm saving money and my marriage.