The way I look at it is this way.
When looking at S3 models, the cheapest one is closer to pure white and expensive one is the yellowest - For me the cheapest one is ok since I like pure white. But lots of people like the more yellow (natural) kind of out put. So Take your pick on that. I do have one of the nat 1B tint and its seems a little too yellow for me. But still very serviceable.
Fun!
If you want to know more, search xml tint in google and read up.
Good pictures of different tints here: tints of some currently avail. XMLs
Look at this Cree doc on page 2 that lists all tints of different xml led’s.