I did my skydiving license with TTS and it was just perfect. All instructors were very friendly, helpful, patient and it was like a big family. Safety was ALWAYS first, the whole equipment & the plane were in perfect condition and the scenery with the lake and volcane is just amazing! A 12'000ft tandem jump was just 150NZ$/170NZ$ (depending on the day time)(march 2005), the best price I've ever seen so far...
I can strongly recommend the TTS DZ! Go for it... :-P