Forgive me - another stroller question

I saw the Mini City Jogger that someone posted yesterday and fell in love with it!

I showed it to DH last night and he thinks that the 3-wheeled jogger-type strollers aren't as sturdy as the regular 4-wheeled types. We have yet to actually really start researching this - I'm just gathering info at this point.

Is there any truth to this? What are the pros and cons to both types?

Thanks!