Goulet pens has just released their own line of #6 Jowo nibs and I really want to try the 1.1 italic. I just don't know what kits use a #6 nib. I usually do the junior series and they use #5.
The full sized Gent, Statesman, Emperor, Roman Harves, Pristina, Imperial, Lotus to name just a few. Just about all the larger component sets will use a 6 MM nib., Now will the JOWO 6MM fit all , thats another question to be asked. They might need tweeking on some.
Wayne, the Roman harvest is one of the harder nibs to remove so don't give up, just make sure you pull hard and if at all possible use a cloth wraped arount the nib and it will come out, I've changed hundreds, to Bock nibs..
If you happen to order one from me remind me and I'll remove the nib for you.