I've not had a problem (yet-knock on wood) with the 407 billing. I use the highway a lot. I like it. Compared to the drivers on the 401, the drivers on the 407 seem to be more courteous. Its very rare to find a left lane hog, drivers move over and let you pass, I've never been cut-off (the 407 is failry busy during rush hour) and drivers will let you into their lane when you signal. Also tailgaters are few and far between. It makes for a more relaxing commute which is well worth the money and unlike the 401 your always moving instead of moving and then idling for awhile.
The other plus is you see a lot of cars that I've never seen on the 401 or in the city (except at autoshows). I've seen quite a few Maybach's, VW Phaetons, Bentley GT's, Aston Martins, Maserati, Lotus, an old Lancia, the new Jaguar XK, various Rolls Royce models, a Morgan, various AMG spec'ed Mercedes, Lamborghini's and Ferrari's amongst others. It's kind of a moving auto show. Especially since most of those drivers are keeping to the speed limit(which lets you have a good look) to avoid unwanted OPP attention.
In the winter, I find the snow on the 407 is removed a lot quicker than the 401 and more throughly. Its also better sanded and salted. I believe the 407 snow clearing and salting crews on the roadway as soon as the snow begins to fall, instead of waiting for a requisite so many centimetres to fall and then going out.