Stroller ? : Phil & Teds vs. Valco

Hi all! Just wondering if anyone has any experience with a Phil & Teds stroller with the rear seat attached or the Valco tri-mode with the toddler seat. DS is 2 1/2 and DD is 1. We currently have a BOB Duallie for long walks and plan on keeping it, but I'm looking another all terrain stroller that is smaller in size for vacations, trips to the zoo, etc...

TIA!
Tina