Here's what I know:

Taxes are very high in Canada.  People in high income bracket (>$100K) pay 50% income tax.  Even if you make around $60K, your taxes will be higher than that of your compatriots in the US.

Universal healthcare is available in Canada.

But, you have to wait your turn for almost any procedures.  Need an MRI?  It's free, but you will get your turn only in few months.  Need a hip replacement?  Sure, government will take of that.  But you will have to wait almost a year.

Plus, you need to be registered with a doctor (general practitioner) for any referrals.  Sometimes it is tough to get a doctor to take you in as his/her patient.  Not enough doctors to go around, I guess.

IMHO: If you can afford a decent medical insurance, health care in the US is the best.  If you cannot, Canada is better.

Side note:  I read somewhere that Singapore has the best combination of affordable and quality health care.  They rank #6 in the world.  Both US and Canada lag somewhere in the 20's.