I have used this lens to shoot images for the last several mini-reviews, an ongoing commercial project, and a number of upcoming Headfonia earphone/amp reviews. It is tack-sharp, feather-light, and cheap as chips.
Wide-open it is slightly sharper than my favourite enlarging lens, the 80/4 Rodagon, which goes used for 150-250$, and which came attached to the not-excellent Horseman VCC Pro. Wide open, it sits at f/5,6, however. At f/5,6, the two lenses are neck and neck.
The Fujinon-EX goes for 70$ USD and down.
It is slightly wider/larger than the Rodagon, and is easier to handle. Unfortunately, it is built to Fisher Price, not to Rodenstock, standards. It's not just Fujifilm's excess use of chintzy plastic parts. It's their insistence on trying to be clever. The 360 degree rotatable mount lets light in to bounce around the inner lens. I had to pad it with gauze. Secondly, its 'illuminated' aperture window lets even more light into the lens. I had to gauze, gaffer tape, and otherwise, patch it. it took me about an hour to get it in ship shape. Its machine quality is poor: parts get stuck much easier than the Rodagon.
Fujifilm's literature says that it is multicoated. A brief glance at the front element will tell you the same. But decent coatings arent' enough. Fujifilm's design was lazy. In a studio environment that relies heavily on flash or natural light, its colour output is muted by 80% and contrast falls into oblivion. Flare creeps into every nook and cranny of the aperture window and 360 mount.
The aperture window is the bastard that lets in all that light
The 360 rotatable mount sits on three ball bearings and lets light bounce around the inside of the lens
If you purchase this lens, you will NEED to modify it.
Below is an image taken by the Fujinon-EX lens, pre-mod. It is of the quite-excellent Cypher Labs Picollo headphone amplifier.
Low contrast and veiling flare obvious across the entire image
Close examination reveals halo flare in the centre of the image which spreads across the entire frame. Then, there's the greying of all colour information, and low contrast between highlights and darks- all unacceptable for what I do commercially.
Modded, however, final images are contrasty, sharp, possess wonderful colour, and suffer very little from flare. I have written more about this lens in action in part 1 of my Novoflex BALPRO T/S review. (Examples that illustrate what this lens are capable of are included in the review.)
Is it worth it? I think so. For 70$ and a bit of sweat, this Fujinon-EX lens turns into a world-class lens for macro and semi-macro photography. Combined with a stable platform like the BALPRO T/S, it is an excellent solution.
It's up to you to decide if it is worth it to you or not.