I'm a very small adult, 5'6, 135, and I use an intermediate NB One95. It's held up perfectly well since May of 09. Before that I used a NB Vapor XVI, and it's still in one piece too.
I'm similar to Devil Dancer. 5"7, 140 lbs. I use a 70 flex intermediate stick, and rarely snap them. If I do replace them, it's usually due to wear on the blade where the composite starts splintering. Other then that, i'm fine.
I'm 5'8" and I've actually gone from a whippy senior stick, to an intermediate, and now I'm using a junior stick (I'm a female so I have problems flexing the stiffer sticks). But one of the leagues I play in is a mens league and I haven't had any problems with the intermediate or even junior sticks holding up when playing against the guys.
I have gone back and forth on this, but at 5'8 175 (s/b closer to 160 though), I like the 75 flex seniors. I tried a couple 67 flex intermediates this summer (Vapor XXV and One95) but the flexes were way off and the smaller diameter was kind of awkward.
I picked up a Sickick OPS and another Vapor XXV both 75 flex, and even after cutting them down, I could still flex them enough and my shots were quicker and harder, and my scoring went way up.
It's worth experimenting, but you might want to try a cheaper stick first, like one of the clearance models.
And FWIW, I chop off about 4-5" from most senior sticks and play with them at my chin in skates. It brings them closer to 90-95 flex.
I'm 5'9.5 180lbs and never dreamed of using an intermediate stick until I saw one on sale last year and decided to try it out.
Wow, the results were amazing. My wrist shot and snap shot have so much more power and the puck seems to effortlessly release off the blade. Slap shots aren't that great but it is worth the trade off...
I'm 5'7" and I use an intermediate stick about 77 flex. I am lightweight though.
I play in a mixed rec hockey league and have no problems with it. It holds up equally as well in terms of wear and tear. I don't slapshot much though - haven't quite mastered that accurately enough to be of use to me
I also cut my stick down (it was only about an inch or so shorter than the senior, so the flex is now higher if that's what you're concerned about.
Of course if you find it too short, then you can get stick extensions.
Just an update, but I've gone back and forth between 65 intermediate and 75 senior, and now I'm using a 75 intermediate (intermediate length but stiffer). Perfect compromise. Doesn't whip out or lag like an intermediate but I can get great flex and snap out of it.
I did break an intermediate stick while shooting but it was a really light high-end stick with thin walls.