14" to 15" tire upgrade success/failure?

I am looking for success (and more importantly failure) stories. I see many posts about upgrading to 15" tires, but I am wondering if TM owners are still having blowouts after upgrading?

I recently bought a used 2007 2720SL and am looking to upgrade to 15" tires after a frustrating trip.

Here's our (all too common) story: Over Labor day, my wife, my 5 month old son, and I were traveling to San Antonio, TX from Beaumont, TX. This was only the 2nd trip in the trailer. We had been traveling 65-70 mph on I-10 less than half an hour, when the left trailer tire disintegrated. It ripped off half of the wheel cover AND the gray water drain piping. This is the point when we should have decided to go back home, but I was determined to make the trip work. So, after changing the tire, we went to PPL in Houston and bought the supplies necessary for me to rebuild the plumbing. I asked if they had a spare tire, but they were out. The rest of the trip to San Antonio was uneventful, and we had a blast.

On the way back, we tried calling several tire stores to buy a spare tire, but they were all closed for Labor Day. Halfway home, the right trailer tire suffered the same fate as the left one had previously. Fortunately, the only thing that was damaged was the wheel cover.

There we were, sitting on the shoulder of I-10 with only 1 good trailer tire. After several minutes of panicking/cursing/wailing "why me?", I had a epiphany. WALMART! I called them and learned that they had a few goodyear 14" trailer tires and could mount them on the rims. So, after getting both blown tires in the back of the truck and unhitching from the trailer, away we went to get two tires. The folks at the Sealy, TX Walmart worked very quickly to get us back on the road, and we made it back home without any other issues.

After this trip I am looking at two options: make an upgrade in trailer tires or sell the trailer. We really like the trailmanor, but are not willing to carry a truckbed bed full of spare tires everytime we take a trip. With the extremely high number of people posting on this site who have had eerily similar problems, I am looking for some assurance that I am not wasting my money making the switch to 15" tires.