I have used an enlarger, a contact frame setup, a professional 1B at EK and an EG&G unit. So, I've covered a lot of territory. I can just say that all of those work for me and have given useful and repeatable results that have been compared over several years. All I can say is use what works for you, and I am happy with the enlarger, contact frame and GG&G that I have. The 1B is probably in the dumpster at Ek.