1) Does using a lot of characters in a battle (through switching) decrease the exp each one gets?

2) Are there any worthwhile rewards for playing blitzball?

3) How do I see if a weapon I buy does more damage than my current one?

4) I just fought the sin spawn (near the coast). How long until I can make use of the Don Tonberry AP exploit? Is that a one time thing?

5) Where do I get weapons with a "capture to weapon" command?