Pre-Cruise Excursion in Montreal to the Laurentians (Mont Tremblant)

[MalibuCA]

I am considering spending one of our days pre-cruise exploring the Laurentians, Mont Tremblant and all villages along the way. I have 3 options:

1. To rent a car and explore on our own.
2. To go on Crystal's Excursion. (Although I am not going until 2010, I looked at Crystal's cruise in 2009 that is identical to the one in 2010, and they have an excursion called "Glorious Laurentians." I imagine they will offer the same excursion or one similar in 2010.)
3. To hire a private guide/driver to take us.

Has anyone done this trip on their own? Has anyone done the Crystal excursion? Has anyone hired a private guide/driver? Which option do you recommend? We generally prefer to stay away from large group tours unless absolutely necessary. Option #1 is certainly more economical than Option #3, but is it difficult to navigate our way around? We do have a GPS system that will help us. Is it an area, however, where it really is a benefit to have a guide telling us what we are seeing? If we should have a private guide/driver, can you recommend someone that you have used? I welcome all advice.

Thanks,
Shelley