How limiting is lack of image stabilization in Pany bodies?

lsundy wrote:

Hi

I've been considering (for a while now) buying a Pany G3/G5 kit, which, together with a wide angle and/or portrait prime, would hopefully give me a step-up from my current Pany FZ-35.

However, what troubles me is the lack of IS in the Pany bodies. if I want the advantages of IS (and I am battling to understand why one wouldn't), then am I not excluding the option of using Olympus lenses and many third party lenses which are not stabilized with the Pany body?