The 125/5.6 W is revered among landscape photographers for its small size and very high image quality. The 135/5.6 has a little bigger image circle. These are modern plasmats. Not ideal for architectural work where a lot of rise might be involved, but generous enough image circles for lots of things. I can't imagine any tessar that focal length adequately covering 4x5. I have a 100 Nikkor M tessar that is adequate for 6x9 roll film, but useless for 4X5; and it's from the very latest series of tessars engineered for view camera use, which logically jumps clear up to 200mm for 4x5 recommendation. I can't imagine using a 150 Xenar for 4x5 except on a press camera where movements are often minimal anyway. 120 Super Angulons are nice if you want a solid rock to sit on when fiddling with your other camera gear.