Star Alliance - Star Alliance round the world/pacific rim trip planner...any thoughts?

As a long term goal, I've been looking at the Star Alliance Book And Fly (http://www.staralliance.com/en/booking/book-and-fly/?) page, idly playing with the tickets/bookings. A kind of round the world trip, or at least Pacific Rim trip is something on the horizon for me (I'll be flying out of Toronto).

My questions are:
1) Has anyone ever made use of this or other flight alliance tools like this and what was your experience?
2) If I'm comfortable buying individual legs, with enough of a cushion in each city should there be a delay, and as I'll be travelling alone, would it be better to do so rather than use the tool? This way I can hack together a cheaper fare, maybe go economy on some legs but business on others?

Thanks everyone.

Many people have used these tools and booked travel with them. They are just fine. Personally, I prefer to use a travel agent to issue my ticket ( it
makes it easier to handle changes later on), but there is nothing wrong
with the Star tools.

A RTW fare will usually be cheaper than a series of one-way fares, unless you are planning a short trip with very few stops. But if you are doing the 15-16
legs that are the maximum, with 12-15 stops, you will not be able to get
a cheaper fare.

Please note that a RTW fare cannot be mixed classes ( unless you can
use some upgrades on your home airline).
the whole idea of the RTW fare. Unless