As you say, I didn't want the BUZZ THUNK of the normal points, I also required computer control, so any solution had to have a digital control side.
I reviewed the tortoise and cobalt and tried one of each but went with the Cobalt as they are much smaller, the DCC decoder is integrated, and you get additional switches to allow the addition of signalling and frog control, all with just two wires to the motor.
In practice they are solid, reliable, throw beautifully and are very quiet. However, I hit 'wierd' issues around programming them, with roughly 50% of the motors I ordered. After many attempts and tweaks without avail, I'm awaiting a replacement box of motors at the moment. An odd issue certainly, but not one that's put me off them, and the customer service from Modelshopbelfast, Gaugemaster and DCC concepts was faultless.