Cerino - I see your point about CC tournaments but I don't know that I particularly agree if WGT's line of reasoning is the weight of the play on stats. As it is they already have that variation when they allow CCs to set up tourneys from the front tees, standard greens and low winds, allowing them to count the same as a WTG sponsored tournament that has everyone teeing off from tier specific levels with tier specific green speeds and winds.
Chuddly - I agree that balls with identical attributes should be allowed. Unfortunately as soon as someone uses up all of those balls they'll be right back here complaining because they ran out, again demanding to be able to substitute any ball.
An argument to be able to substitute a ball with lesser attributes does not work either. Many players, myself included, can't handle a 4.5 spin ball as well as a 3.0 spin ball. Substituting a lesser spin ball in the middle of a round actually improves our game.
We should be able to substitute at will in a practice round though. Combined with the mulligan feature it would be an excellent learning tool and increase ball sales as players use up balls learning what equipment and shot combinations work best in certain situations on certain courses.
Someone also stated that WGT doesn't make any money with shots taken by the free ball. Not on that specific shot but think of the ball usage that has come from the current rule. How many players quit the round and start over? They are using up those balls before the substitution, quitting, then buying more or playing with a different ball before posting a legitimate round. In most cases that's an extra 30-60 hits for each completed round. It adds up in WGT's favor.