We have both the Bob Revolution single and the Bob Revolution Duallie. LOVE THEM! They roll over EVERTYHING! We have a Toyota Camry and both strollers fit in the trunk. We just have to remove the wheels on the Duallie to make it fit. But the wheels come off easily.
My kids are 5 and 3 and we have mostly been using the single for the last 2 years. When my kids were 3 and 1 we would put my 1 yo in the seat and then put on 3 yo on the foot rest. The love riding like that.
Love the swivel wheel and the easy pushing and manuverability of the strollers. We have taken them both to amusement parks, camping, walking, flat trails, to the beach (it rolls over sand pretty easily), and to the mall. I used them both as my everyday stroller. We have used the single stroller the longest (1 year with just my son, and now 2 years with both kids either taking turns in it or riding it piggy back style). We used our Duallie for about 1.5 years until my daughter was about 1 years old.
REI.com has a 25% off plus free shipping sale on the Bob strollers on Labor Day and Memorial Day weekends. You can free ship it to your local store and they will set it up for you.
I also highly recommend spending the extra buck for the handlebar console for keys and drinks.
Also try craigslist for used ones for cheap...but if you see one on there, you need to act fast since they sell FAST!
Also the resale value for Bobs is pretty good. You can resale it for about 50 to 75% of the original purchase price.