I have a really hard time imagining a scenario where a TFSA beats an RRSP.
If you have $200 per paycheque to save, and you're earning enough to be in the 50% tax bracket, you can do one of two things:
a) Put $200 in a TFSA
b) Put $400 in an RRSP
The money will grow. Let's say you wait one doubling-time until you retire.
a) There's $400 in your TFSA
b) There's $800 in your RRSP
So now you withdraw your money. Your RRSP will now be taxed, but the taxation level won't be at the 50% level it was when you deposited it. It'll be at some much lower level, assuming you're living a reasonably Mustachian life.
a) You get $400
b) You get - I dunno - $700? More than $400
The only way the TFSA wins is if you already have some kind of guaranteed pension plan that puts your retirement income in the top tax bracket anyway. Then your RRSP gets taxed right back down to the level of the TFSA.
The advantage to the TFSA, however, assuming you filled up your RRSP, is that it's a lot easier to withdraw from. So if you wanted to have that "emergency fund" thing that the Dave Ramsey types are so fond of, you could use the TFSA for that purpose - AND you get to invest it and watch it grow.
If someone has another angle, I'd love to hear it. As far as I know, it's:
a) fill up your RRSP
b) then use the TFSA