As Bob (aka Rustic Eagle) stated in post #2, taking the time to look into what your TV's capabilities are before purchasing a new HTT or TT is a smart move.
Since you plan to travel at high altitudes, keep in mind that a gas engine will lose approximately 3% of horsepower (HP) for every 1000ft above sea level. So, at 10,000ft, you will lose approximately 30% HP. This is another factor to consider as you calculate your towing parameters and/or plan your travel routes throughout mountain country.
2004 Suburban 2500 LT 8.1L/4.10/4x4
Putnam XDR Class V, Equalizer 1400#
2006 Jayco Eagle 264BHS
Iota DLS-55, Progressive Industries EMS-HW30C, Trimetric TM-2025