I'm a Canadian who immigrated to the US in 2006 and in the last two years have had some experience with the US health care system as my wife had some health concerns and I was fortunate enough to be blessed with beautiful twin girls last May. Comparing the two it's really a no-brainer for me, the Canadian system is much better, however I'm not convinced it's optimal, and I think some sort of two tier health care would probably provide the best of both worlds.
Firstly, to compare the two I am going mainly by personal experience, and there are some significant differences. Firstly, the quality of care was comparable in both countries, however the creature comforts in the US were much more plentiful. When my wife went in to the hospital for her pregnancy and complications related to it she was given a private room, with a telephone, TV, DVD player, WiFi access, couches and chairs for guests and a full menu room service. In comparison, when my dad was in for surgery he shared a room with three other people separated by curtains. If you wanted to use the TV or a telephone you'd have to pay extra and there was no access to a DVD player and only a few chairs for guests. The reasons for this are clear, US hospitals are focused on attracting customers and Canadian hospitals are focused on reducing cost and have no need to attract new business.
In terms of cost, I've never paid for any hospital or doctors visit in Canada, you're still required to pay for prescriptions, eye care and dental however insurance given by employers generally covers these and you can pick up individual insurance as well if you feel you need these services and don't want to pay cash. In comparison, I had a mind boggling $4000 just for the hospital visits, not to mention the $1000 a month we're paying, and which doesn't include co-pays for follow up visits, lab work or the hassle we've had to deal with because of double billings and mistakes made by our insurance company! For example we were eligible to receive a Synagis shot to vaccinate against a particularly nasty bug for infants. When the doctor put in the request we got a call from the insurance company about a $250 copay per shot per child, which worked out to be ~$2000 for the twins. Now we certainly couldn't afford that so we told the insurance company we didn't want the shots. About 20 minutes later, they called back to tell us they would waive the fee, which from a rational perspective makes perfect sense, it's better the vaccinate then bear the full cost of hospitalization and we should never have had to ask for them to waive the fee. So once we had confirmation that the copay would be waived, we went ahead with the shot. This did not stop the insurance company for sending us a bill however, and we've been on the phone with the three times already while they escalate this through their internal red tape. Every time they assure us that it'll be taken care of, and every time someone else calls with a minimal understanding of what the previous person has done or said.
Needless to say, I'd vouch for relatively stress free government run health care system with bureaucratic inefficiencies (and believe me, they exist and can provide ample frustration) then the Gong Show that is the US health care system. When the chips are down, and I need care, I don't want to be thinking about how much it's going to cost me, I just want to know that quality care is available to me when I need it. When the cost of both systems are compared, it's enlightening to note that the extra taxes Canadians pay work out to be approximately what Americans average for insurance. As numberlady said, when the Canadian government writes the checks, they also set the fees which are standard no matter who's providing the service, and the problem isn't with the doctors themselves but with the insurance companies which create a gluttonous middle man.
And to whoever said "Healthier lifestyles anyone?" I can understand the sentiment, however it's naive to believe that living healthier is going to help people who really need the care. My wife and I have a friend in the Parents of Multiples group that we belong to who recently had triplets and at birth they had significant complications. Their insurance stopped covering care about three days into treatment and they racked up millions of dollars in medical bills over the next few months during which you can imagine they were also dealing with loss of income from the stress and complications related to their children's care, and the death of their son after 6 months of struggling for life. Somehow I don't think eating more greens and going for a jog were really viable options for this couple who's financial lives have been destroyed by this tragedy.