
I have a Metro air force master blaster (twin motor at £300) that I use for my Newfie. Very happy with it and yes it does blow warm air as the air moves over the motors inside the case to cool the motors. Depending on the temperature of the area you are using it in will effect the temperature of the air blown out.
The power output is just within my limits on the house mains due to its amps and the air velocity is very powerful and able to blow with care all the dust and crap out of his hair. Its also quick for removing all the water after a bath.
Be warned the velocity of blowers can harm your dog if directed towards their face, ears and private parts.
Got mine at
http://www.christiesdirect.com.
However I would think a single motor would be fine for you.
My Newfie loved it straight away and just stands there enjoying the all over body massage.
Being that I was once a calibration engineer working with velocities/air movement and wind tunnels I looked at various blasters, the motor output, type of impeller assy/motor design, their diameter of hose, its length and the most important part the funnel on the end. Just like the wind tunnel the funnel on the end is what has the last say in the air velocity speed regardless of motor power which too has a good part to play.