Hi,
from some time I have started srsing core 2k steps (+200 each) and now I have spotted that there is optimized core which have different sorting - vocab with same kanji are one after another.
Should I switch to the sorted/optimized, what are the difference in these methods? Which one you use?

I finished the standard Core2k, mostly because I started it after I saw the optimized decks and didn't know how to switch over. It wasn't too hard.

That said, when I do 6k I'd like to try one of the optimized decks. Just not sure how to do that while keeping the progress of my 90% mature Core2k deck.