Although the name is used interchangeably, they are two different varieties from what I understand. Just not too long ago I read that the descriptions for each are totally different.

Oh okay! Thank you for letting me know. I'll probably just use the name Nebel's Rainbow from now on.

I have a Lei Rainbow from Upland Nursery, and a Nebels Rainbow from Derrick Martin. Will see how they bloom, and return to this post. Hope they're not the same - my space is too limited for duplicates. If they end up being the same I'll offer one for trade, or sale, (for half of what I paid for it, plus postage) .
Cyra