If you are in cities the fido network is very good but if you go deep in the
country you will loose it quickly.  Check the covering maps at:
http://www.fido.ca/portal/en/packages/canadaCover.shtml

The sound are better than Telus and the rates also.  You will pay 10c for
long distance instead of 25c.

That's something Telus not offer at all with their american-only CDMA
system.  But beware of the charges.  If it is just to emergency or a few
calls that's ok but don't use roaming too much unless your company pay for!
Korea is different since they use...CDMA phones but not the same as telus so
you need to rent another phone.
Check at the fido web site in the roaming section.  You will see all the
rates of the differents roaming parteners around the world.  Look at all the
countries they offer, even palestinian authorities (at just 30-43c/min).
Try that with Telus!

http://www.fido.ca/portal/packages/international.jsp?lang=en

Sadly they change the incoming prices of calls like in France where it's
free to receive, in the past you just pay the regular .54c canada-france
long distance and now it's 1$.  Maybe for countries where you pay to receive
it's better but not with europe.
Anyway if you plan to stay for more than a week or two in a country, it's
better to unlock your phone (very easy in europe or asia) and buy a local
SIM card.  Foward your fido calls to that number and you pay less (just long
distance to receive and local rates for the rest). This will also give you a
local number, easier for the people in the country to call. And buy a local
long distance card. NEVER call back to canada with cell phones rates, it
will cost you anywhere between 1$ to 12$!!!

I'm in Vancouver so I don't know how good or bad the V60i is in
Montreal.

Anyways, the V60i is a solid performer with regards to its RF and
audio quality, especially on Fido. Friends tell me that I sound like I
was on a landline phone when I talk to them using my V60i. It has one
of the best RF quality since the P280. I never has any dropped calls
even on a busy or spotty areas.

Go here: http://www.fido.ca/portal/en/info/Discover/CoveragePrice.shtml
to find out call charges i nthe country where you're roaming.

When roaming, it is suggested that you bring an unlocked phone and get
a prepaid service in the country you'r visiting. It will be a lot lot
cheaper for you if you do this.

BTW, South Korea is using CDMA. You will have to rent a CDMA phone to
be able to roam in that country. Fido will tell you where to rent a
CDMA phone.

Hth.