Is is better to put them in a fish bowl, or in a cycling tank?

Okay, so here's my issue, I have a 10g aquarium that's all the way cycled and aged 8 months that my fantail goldfish lives in. I bought (day before yesterday) a 29g tank and am trying to get it set up and cycled. The problem is that (technically) yesterday my parents bought me two "buddies" for my fish and her new tank. They don't understand cycling OR isolation. I had planned on doing this all myself, cycling the 29, putting Gremlin in IT and using her old tank as the qt for ONE other fish. So I have the fish (both about an inch long) in a fish bowl with cultured gravel from Grim's tank and a bubble stone. Is it safer to put them in a fishbowl where I can do VERY frequent water changes to keep levels down, or in the cycling tank, where I need to let the ammonia and nitrite levels spike and fall again?