I really like the Jetboil Flash PCS setup, it packs great and is super light. Boils 16 oz of water in 90 under 2 minutes, at an elevation of around 6000 feet (my kids were timing it during bow season, they thought it was awesome)!
Best of Luck,
I have the Jetboil SOL. I love it, boils fast, lights easy, light weight and no problems at altitude as long as the fuel stays warmish.
I have the SOL Ti.
Light? Ohhhh yeaahhh.
This thing is sexy.
I like my Jet Boil Sol Titanium. Fast boil, light, piezo igniter starts the stove easy. Only thing I'm not fond of is my lid falls off easy after it's all packed. Overall it is a awesome stove though.