Equifleece are very popular with 'poo' owners due to the fact they fit well and wick away moisture and keep the dog dry. Hattie has had hers for a week now but not warn it. Walk your poo towel him off and he will be fine most use the equifleece to keep off the worst of the mud and keep dog warm following a walk.They are made from good quality polartec fleece and when put on a wet dog whick away the moisture leaving the dog dry and warm. One thing I have discovered is the absorbent nature of the poo coat! There is no such thing as a free lunch. My terriers shed hair for England but were easy to keep clean, Hattie seems to absorb mud but does not shed hair! I find the laundry liquitab containers very good for dipping muddy paws. Can't wait for poo two(!)
I think it depends on your dog. Betty does shiver when it's freezing but mainly if she's just walking or I stop to talk to someone. If she's chasing her ball she wouldn't feel the cold though. I mainly use it to keep her a bit cleaner and drier on her body as it's easy to use wash dirty legs off!!
I personally don't think they need a coat to keep warm...nature a does great job of that already. However I use a rain coat to keep Obi dry and it was well used today for sure! Others use an Equafleece which is also water repellant I believe and helps keeps the fur covered up and therefore cleaner. HTH
We have a very cheap coat for Olive that i got for 60% off since they were getting rid of their winter stuff. We honestly haven't used it that much. I find that if it's cold enough for her to need it she is cold with it on anyways! It's the wind that makes her shiver and I'm sure the coat helps, but not enough to make a big difference.