I am having quite a few issues with my upgrade, is there away to do i clean install of 4 and import just members and posts from 3 with out any settings?

There is no official way to do it.

What are your problems?

All the issues have been reported so hopefully will get in update soon.

I'm interested in doing this myself. I'm running a 6 year old forum that's really looking worse for wear, and I feel like the best approach would be to install IPS anew and restore the content only. It'd maybe be kinda cool to have an an IPB/IPS -> IPS migration tool to go along with the other tools.

The converter could do it although its not as you'd think as it does offer a merge facility but that's intended for mutliple boards and they need to be the same version, so it would not work for 4x in this way.

If you're having 3x to 4x upgrade issues it would best to simply await the appropriate fixes as required for this though, as running the upgrader is always the best way of upgrading.