Sounds like you'll end up getting tires that serve you well. I've been towing an assortment of trailers for over 35 years now, and only ever blown a trailer tire once, and that was because I nailed a tire eating pothole with my boat trailer on the way back from lake Powell just outside of Hanksville.
So far I've towed my current Timber Ridge Travel trailer a little over 10,000 miles since I Purchased it in the Spring of last year. It has ST Goodyear Marathons on it which have worked flawlessly, and currently show little to no signs of wear. One big plus is that Outdoors RV tends to overbuild their products a little and they put tires on the trailer that have a combined load capacity of approximately 3000 lbs more than what they would have to carry at the trailers GVWR. My experience as mentioned has been that if you keep with within the weight rating of your tires, and keep the air pressure maxed out you'll get good service from your tires whatever they type.
Finally, as for LT tires, I've destroyed over a dozen of those over the years on my trucks, but that's because I tend to drive off road on occasion. In fact, I had to replace one of the ones on My 2011 Dodge Diesel at when I cut the sidewall on a rock while towing my RZR on a dirt road down in southern Utah. Seems I should have found a trail head closer to the pavement that day. While they may be tougher than Passenger tires, they are far from indestructible.