Iona is eye-oh-na, like the island in Scotland where the name actually comes from. I think it's really beautiful, I have close family ties to Scotland and my mum loves that island so it's a definite possibility for me to use one day. It's spunky and unusual, but pretty simple.
I used to look after a little blonde haired blue eyed Iona in England. Her bigger sister was Isla- way too close for me.