We bought our second HTT last year. Our old one was an '03 purchased new. We had it for 10 years, no leaks.
Check those negative posts. Almost everyone of them will be an opinion from a non-hybrid owner. For the most part, hybrids do not have water problems.
If anything too often people don't season their tenting when new. If you do have tent leaks then you can use seam sealer. Otherwise there is nothing to do, the bunk ends are vinyl. Also many people confuse condensation with leaks.
2013 Jayco Jayfeather X20 E, 2008 GMC Sierra 1500 Crew Cab Z71 SLE