Funzy said:
But some people said they can go until 34 waist
They cannot. Not without modding. Tape-to-tape, the back of Huggies Overnights 6 measures about 17 inches. The width of the taping zone in front is 6 inches. Assuming roughly 2 inches of overlap to secure the tapes, that's 21 inches
before stretching. Which brings me to: The tapes on these diapers aren't very stretchy--nothing like Pampers. There is absolutely no way that you're going to get 12 more inches out of them. You'll get about 4 total (two on each side), which brings you up to 25 inches. Some people try taping to the "ears" of the diaper (the tab-looking things on the front sides) rather than the taping zone. That'll get you another few inches, but the adhesion isn't very good there, and the tapes will usually pop loose after a very short time.
Last but not least, the rise of Huggies Overnights 6 is 20 inches, and that includes any necessary allowances for "man bits". That's 3 inches shorter than GoodNites L/XL, which for adults, is already on the short (low-riding) side.
If you're determined to stretch into a baby diaper, you're pretty much stuck with Pampers. They'll still be tight, but you should have no trouble taping up Baby Dry 6, which is probably the most common "large" Pampers diaper you'll find. As a testament to the stretchiness of Pampers--and to my stretching skill!--I've several times managed to stretch into Baby Dry 6. I have a 38-inch waist, but because of the low rise of the diaper (it's longer than Huggies, though), it's actually going around my 44-inch hips. Needless to say, these diapers are exceptionally tight on me, and it's not my preferred way to use them, but I still find it amusing that I can "wear" a baby diaper without modification if I want to.
YMMV!