Running Buggies for Off Road

geekpie

Hello,
We've very recently had our first child and are looking at getting an off-road style running buggy to supplement the Peg-Perego travel system we've already got (does a great job but not suitable for running or offroad really).

Shortlist:

Mountain Buggy Terrain
Out n About Nipper V4 Sport
Out n About Nipper V4 (single / 360)
Boogaboo Runner
Baby Jogger Summit x3 running buggy
Britax BOB Revolution Pro
Thule Urban Glide 2 Stroller
Bumbleride Speed
Thule Glide 2
Graco Relay Activity Stroller
Hauck Runner
Phil + Teds

It seems like only the Nipper V4 Sport and Boogaboo Runner have the larger bike type wheels which look a lot better for off-road, but both have fixed front wheels (no unlockable swivel).

The places we want to run/walk are rocky tracks so my gut feeling is to get the Nipper V4 Sport but how much better is it for running on rocky tracks than the Nipper V4 single/360 for example? Are the larger wheels worth it for the sacrifice of having a fixed front wheel? (chances are, if we're in a supermarket situation, we'll be using the Peg-Perego anyway).
People seem to swear by the Mountain Buggy Terrain, Britax BOB and Hauck Runner too, but again they haven't got the huge wheels so guessing they're just running on flattish tracks…?

Thank in advance.