I know that out of experience, most people catch Dialga/Palkia as easily as a Lv. 2 Starly using an Ultra Ball. I feel sorry for everyone who listened to Nintendo and used the Master Ball. Giratina was exceptionally easy for me as well, I killed the first time but caught with one Dusk Ball the second time. Then Regigigas was easy and since it was the last one, I reset for a chalenge(sp?) Took me two days. Heatran was the hardest IMO, it took me a week. 50% of the time, it killed itself with Struggle lol. But I'm ranting here.