[Kraftwerk]

I use SPD's for long commutes and when I want to make a lot of on the bike off the bike fast errands. The shoes are pretty walk -able.
Look Keo Carbon on the road bike -- 25 miles or more rides. Feet hardly ever touch the ground on those rides.
Then I still have toe clips if I need some decent shoes at my destination. (Pedals are one of the reasons I have 7 bikes! )
Lately though I use spd's and bring a pair of shoes, works well and I can still walk a bit in the spd's.

As far as clip-less pedals go you will just be much more efficient with them. In P-car terms: YOU WILL GAIN HP!

BTW -- nice to see how many great Pelicanites also seriously ride bicycles.