I bought that one for my wife years ago specifically for spices. *Works a treat for almost anything.
I just asked her for feedback from the things she has learnt over the years...
- Be careful with Star Anise and anything like it with large irregular particle sizes. *They really need to get broken up first in a mortar and pestle or similar.
- Some items are best done by running them through on a very coarse grind first and then regrinding on a finer setting.
- It doesnt cope well grinding things that are particularly oily.
- Run rice through regularly to clean it out (especially with oily substances).
- Nuts dont work at all due to their high water/oil content.
- If youre concerned about mixing spice flavours at all, youll want to run some rice through between batches.
- And be sure to make certain the lid is on when grinding things like corriander seeds. They go everywhere!
Oh, and to answer your question about sea salt and pepper corns... *the thoughts are that there wont be any issues with pepper at all and only with salt you might want to either just do a coarse grind, or perhaps multi stage grinding for sea salt.
Hope that helps,