I used an Elwood years ago for everything up to 5x7. It was just okay for 35mm, but when the negs were bigger, it soared. My lens for big pics was a Kodak Ektar. For smaller negs, I had a Nikon f4 for 35mm and a Minolta enlarger lens for 6X6 cm. The enlarger itself was literally cast-iron and had a big base.
I have to sell the complete set or throw it away now. If anyone in NYC is interested, let me know. Maybe even a school photo department would like it as an example of diffusion enlarging.