H. P. , Jul 04, 2004; 10:50 a.m.
General speaking, condenser enlargers give greater sharpness while diffuser or cold light enlargers mask dust and spots. I've only used the Ic and that about thirty five years ago. Fitted with a Componon 40 it produced 20x16s that were sharper than I could have wished for but Oh! How it showed up the smallest spec of dust!
Given a suitably good enlarging lens, I'd imagine you could be very happy with any of these but you'll want a good spotting kit to go with it.