I AM NOT REALLY SURE I UNDERSTAND WHAT YOU SAID ABOUT LENS PERFORMANCE.
YOU SAID THOSE PROCESS LENS FALL APART WHEN YOU ENLARGE?, BUT JUST BEFORE YOU SAID SOMETHING ABOUT VIEWFINDER?.
I ASSUME YOU ENLARGE FROM LARGE FORMAT NEGS, AND YOU CAN SEE LENS FALLING APART?, WHAT SIZE DO YOU PRINT?, I WOULD LIKE TO SEE YOUR PRINTS SINCE YOU SEEMS TO BE KNOWLEDGABLE AND DEMANDING. I AM AT THE MOMENT BUILDING AN 8X10 POINT SOURCE ENLARGER AND NEED ALL THE INFOS I CAN GET.
FROM 35 TO 4X5 I ONLY USE POINT SOURCE LIGHT, AND FOR SMALL FORMAT THE SHARPER LENS I HAVE TESTED IS A COMPUTAR 3.5/65mm

AS FAR AS TAKING I GET GREAT RESULT WITH A APO-NIKKOR 1:9 f= 455 PROCESS LENS (8X10 CAMERA)

HOLDEN