Phil & Ted's HELP!

Seeing as the family is expanding and the big Disney trip is on the horizon, I am frantically trying to decide which of the many Phil & Ted's inline buggies suits the Stow family best. I must say, I am not too impressed with their website, as it lacks a comparison of the inline strollers and all seem to have the same function/description. (Some have 4 wheels, some have 3) Baby Whiz seems to have the best description of the various set ups. Emily is certainly past the point of stroller riding, but at Disney, that's another story. My girl is TALL and 47 pounds, so we need something substantial that provides comfy riding in and around the Magic Kingdom. But then when the little man arrives in a few months, we'll need a stroller that can accommodate both Aidan & little newborn brother. The Sit N Stand is pretty terrible for walks. It's basically a "take to the mall only" stroller. I hate how bulky and long it is and I hate the steering. Looking for something sturdy and easy to push on major get-back-in-shape walks in September - Fast walking, serious walking, miles of walking. So which Phil & Ted's do you have? And which one would you recommend for the Stow family? And believe me, this is not a cheap stroller. So help me make the right choice!!