Which Baitcast Reel to Learn To Cast On

[mike234]

I have a six year old grandson who wants to learn to use a baitcast reel. He has been using spinning reel and can cast as good or better than myself. I can not decide which baitcaster to give him to learn to cast with or do I need to but a different one.
I have the Curado E's 205, 207, and 50. Also have Core 50 and 100mg and the Calais 100 and 200. Also have Daiwa Zillion reels and every size ABU Ambassadeur made. Think the Ambassadeurs are too big for him and probably the Curado's and Calais. Was thinking of using the Core or the Curado 50 to let him start with or is there a better reel for young people to start with.
Noticed Bass Pro have a baitcaster that they claim will not blacklash and is good to use for learning reel. This is my first time to teach someone how to use baitcaster and wanted to get him the best reel possible to start with so he will not be discouraged. He can cast one somewhat but can get no distance or accuracy with it and if tries to get more distance always gets backlash.
Any suggestions will be appreciated.