I've got the dash too. I recommend you go to the shop, have a look at one and measure it to see how much of your boot it will take up.
I personally think the jogger strollers are great for walking on sealed surfaces - footpaths & roads & at the shops etc. When we take ours off-road it feels a bit unsteady with the doubles kit on. (We've got the toddler seat on the front atm cause Phoebe is lying down).
But I like the P&T seating system - I didn't want a side-by-side one because Natty won't be in a stroller much longer, and when she's at childcare I can just have the one seat.
I find it easy to fold/unfold and the toddler seat is very easy to attach/detatch. I don't find it any heavier than the bertini shuttle I had before, but there are definitely lighter, more compact strollers out there.
Go have a look at one in the flesh if you can HTH.