I have a P&T vibe. The brake on the vibe is very easy compared to the other models. We got ours online ubercheap (>$700 including the double kit)
I like it because it really is super easy to fold up - WITH the 2nd seat still attached.
Whilst i thought it would be weird having one child slung down underneath, it is fine. And they have so much more room than some of the toddler seat ones. My older child prefers being in the small underneath seat, because that way he can chat more easily to me - his choice, and someone did once tell me i had them around the wrong way!