You have a Blue Roo and a Splash Roo there.
If you have Blue hens, you will have more variety of color if you keep the Blue.
As for type and conformation, I can't see much with the Blue, but they are only 6 months old and they have some time left for maturing.
The Splash is pretty, but if you breed him to Blue hens you will get blues and Splash only. If you breed the Black to Blue hens, you will get Blue, Black and SPlash chicks from them.
It all depends on what you want.
If one has a better personality or treats the hens better than the others, then I would lean toward personality. I just had to put down my BLue Ameraucana roo this week because he was horrible to the hens and other roos. I don't want to keep breeding that in, so he is gone. It is a very bad feeling to have to do that since he was my only one, but I refuse to keep a roo who is that much of a problem. So, choose wisely there.
Good luck.
They are both good looking, pretty boys.
OH and you WILL get blue eggs. If they are purebreds, that is one feature that makes them so.