Buy you a American made tire, Goodyear firestone, michallen, etc. and make sure it's a radial also, you'll get more miles out of the radial and it makes the trailer ride better too.
On blowing 5 tires. I'd say it was a combination of make of tires, type of road, and heat.
For myself, I blow four tires in one month. Same tire each time, and about the same place in the road too. I had some important trailer tires on my cattle trailer, and I blow the back drivers tire out on my second load of cows each time. The cap would pill off or the side wall would give out. Got pissed about it and put some firestones radials on it. I've ran two sets in the last 10 years and I have not had a tire blow out on the road as of today.