Apo Nikkors are also a superb choice sharper than conventional enlarging lenses if you don't need fast printing speed, and they're way cheaper
than Apo EL's. There are a couple logistical problems with going to these extremes, however, that most darkroom folks don't factor in. Apo EL's
are rather bulky and heavy, so might actually weight-deflect the lens mount on many common enlargers built less massively than a military tank. The other is that just too much MTF is not always a good thing, because every little blemish or nuance in your carrier glass or film base itself will come into resolution, including anti-newton patterns visible in open skies or other textureless areas in the print. And if you think you're going to avoid this by not using carrier glass to begin with, then you just wasted all your money on a fine lens anyway, and might as well put a coke bottle in the lens position, cause your prints are never going to be critically sharp anyway. I've actually had one of those rare
opportunities to buy a small (105) Apo-EL relatively affordably, but passed it up because it didn't really meet my own needs, even though I do
have a couple of enlargers built by tanks. Now a 360 version would be nice, but the only one I've ever seen for sale went for ten grand, so I'll
just have to be content with my 360 Apo Nikkor for nitpicky precision, and my bulky 360 EL Nikkor for speed. But in color printing, minor nuances of contrast can be tweaked simply by choosing between such lenses, even from the same mfg.