I have heard of some sun conure learning to talk and want to know if there is a pretty good chance that I can teach Rio to talk. I never trained a bird to talk or whistle before. Is it worth my time to actually spend time talking to him? How can I know if he is picking it up or not? He isn't really vocal but he does make the cutest sounds when he is sleepy or cuddly.

I don't really care if he doesn't sound clear when he talks. I like the scratchy bird voices. I think it's cute. I just want to know if he has a potential to learn it.

Here is a little article on that subject...thought it might answer your questions
http://animals.mom.me/sun-conure-ever-talk-4542.html

I think it's worthwhile to talk to him whether he ever learns to talk or not. Birds in a wild flock would vocalize to each other, so talking helps meet his social needs. You don't have to chatter nonstop to him of course, but talking to him helps to make his life more interesting.

I've taught my birds to chat... Obi is doing really well
at it... its just a case of repeating the same sentence
to him for a few days...

Like: Rio is a good boy.... what you doing Rio...etc.
once he gets the hang of it he will pick up
more and more....
Give it a try!
Make's a bird very interesting for us to listen too.

I was just going to post a thread about that I still will anyway you could teach Rio to talk same way you would teach a baby and show him what the word means like do you wanna scratch and then give him a scratch.