Hi David and others
I went back and retried the Sommerville Lincoln 757. It is a bit better than my original rating. It has lovely flex and it gives medium to fine hairlines. Have to concentrate on being liight on the upstrokes but other that a real lovely nib and holds plenty of ink
I would rate it probably 9/10 now
Thank you for referencing a very important point in searching for "good" or "best" nibs.
There is no best nib.
Some nibs are better for achieving a particular end or style of writing, on specific paper, using a particular ink or class of ink, for a particular person at a certain skill level at a point in time. Over time, just as you have found, I've found my rating of a nib has changed. The nib didn't change--I did. Perhaps what I was trying to do changed, my skill level changed, the other materials changed, and so on. A Zebra G may be a better nib for someone than a Principality, though the latter may cost ten times as much for other reasons and be considered a better nib.
I only mention this for a couple of reasons--for people with limited experience with the broad choice of nibs, don't go chasing after a nib just because someone says it's great, or the highest rank unless that person has wide and deep experience trying out these nibs and know what they are trying to do with them. Those nibs may be best for them, but not for you. By all means try out new nibs recommended highly by knowledgeable penman to see if they are right for you. And rank them for your own benefit, and, with caveats in place as to what you are using them for, for the benefit for others. I love threads like this that offer opinions as to nibs I have never tried. There are so many to try.
In the end though, don't get too hung up on what is the better or best nib. More practice will lead you to better results than a better nib.
