Aside from all the points made about compatibility you will have to give equal time to both birds. Me personally couldn't see giving Salty less time with myself, he would not like that. I give major kudos to those folks who can work out sharing their time with multiple birds though. It's certainly not for everyone. Good luck!
That's the problem I'm having with Stephen and Romeo.
Stephen just doesn't like having less attention because of some "other stupidhead bird that won't stop screaming! I'm SUPPOSED TO BE THE LOUDEST"
But we're making it work. Mostly by me adjusting my schedule a bit. And just sucking it up and making it happen.