Single or double jog stroller

I've got a baby jogger double that I use with a 4 yr. old - 43 lbs. and a 3 yr. old - 33 lbs. They fit in it fine with room for various stuffed animals, sippy cups, snacks, etc...Usually Im the one that's done with it before they are. It's tough work! They are much better at sitting in there while they're occupied or tired. There's still room to grow for both of them but I think mine is a bit wider than most. It doesn't fit through a single doorway - we need double opening doors to get into anywhere.

Thank you all for your feedback.

Kristin - what stroller do you have?

Jenna - I almost bought a Chariot when I had my first son.  Do you have one that converts from jog stroller to bike trailer (or do they all do that?).  That almost sold me on it the first time, but my SIL gave me her old job stroller and we bought a Trek Solo Bug trailer (which I think is awesome).

We don't have a store that sells jog strollers so I'd be purchasing online (most likely).  I may have friends who have a BOB so I could probably try that out.

Thanks again.

The Chariots are super expensive.  If I am reading the website correctly, you pay up to about $900 for the chassis and then the conversion kits on top of that.  I was looking at the cross-country models as then seemed to be the most suitable.  I want something predominantly for jogging and secondarily for riding and I cannot really figure out which would be the best one.  Any ideas?  FYI I have many miles of paved rail trail and crushed gravel rail trail to ride and run on.  So I don't need something super-durable.  I am after a fairly light one that is easy to push.

Thanks for all the feedback so far.