I thought Koolies would be a great fit for me but after living with one I would not seek one out. Yes they are great dogs but there is just a certain 'yay life' trait that doesn't gel with me.
And the noise, oh the noise.
A breed I never had an interest in till spending time with them was GSD's. where I train there are several and it seems like most of the other trainers have them to (working lines) and they are beautiful dogs with a great even temperament.
I think they are still too big for me though and if I was going to get a dog for a protection sport I would have to go with a mal.