We own a Valco Trimode EX and LOVE LOVE LOVE it! They are not common in our area, although we are starting to see more of them, and I'm always getting complimented on the look of it and asked what it is. We have the all black version from 2009 and it really is sharp looking. What I love about it:
The wheels tackle any and all rough terrain we have tried and we have tried some rough stuff! Also love that it comes with it's own air pump that discreetly stores under the seat.
Awesome canopy and zip in UV sunshade (definitely worth the extra purchase!) - DS1 was born in June and I knew we would be outdoors immediately, so the UV shade was a real selling point. It also creates a cozy little nap spot with a little more privacy for the little ones!
Add on Joey seat with canopy - purchased this with the arrival of DS2 and am pleased, although I think we could also do without. DS1 usually prefers to walk, but it has come in handy when he has tired and I've been out with both boys on my own. I usually babywear the little guy, but again, it's a nice option and well made. DS1 is comfortable in the seat and still had considerable head clearance, but I'm not sure how comfortable a "bigger kid" would be.
Bassinet is awesome! Loved using the bassinet and that it came with it's own bug netting and rain cover. Everything is really tailored to the different pieces and the fits are great. It was easy to switch the seat and bassinet out.
Standard options - Zipon storage bag on back, rain cover, air pump, infant head hugger. Did I forget anything?
Negatives:
It's not a small fold nor light by any means, but what all terrain stroller really is? I was able to manage the stroller no problem in and out of our SUV even 9 months pregnant.
And that's really the only negative for us!
Good luck with your stroller search and sending baby dust your way! Oh, and I think I heard they were coming out with a new color for the Trimode in 2012, but can't remember where I read that!
Here's a short blog review of some AT strollers as well:
http://www.sheknows.com/parenting/articles/850363/best-all-terrain-strollers