You're right, there is no convincing Uni-Vibe tones for a box that's slated as the be all & end all of modulation, since the first modulation stomp box effect that ever hit the streets was the Uni-Vibe made by Shin-ei and I have yet to hear a convincing replication of one from any clone or modeler box after having tried many expensive clones. The Line 6 MM4 comes closest in modeler type efftecs and the Fulltone Deja 2 comes close for an analog pedal as does the Sweetsound Ultra Vibe but all of them are still missing something and not quite nailing it for some reason though they all claim to do so.
This is because a Uni-Vibe is a 4 stage phaser and the ModFactor only allows up to 2 stages of any effect. Aside from the 4 stages, there are other factors like the electronics used, their variances back at that time on the original. Patch 12:2 "Lounivibe" is supposed to be an approximation of a Uni-Vibe but doesn't come close even near as much as the Digitehc Hendrix pedal does. Probably patch 2:2 comes closer though a good makeshift sound that sounds pretty awesome is if you run a Fulltone Deja 2 (Uni-Vibe clone) into the Modfactor set on the Patch 6:2 Rotary Leslie patch. Now that sounds about as close to Jimi's "Hey Baby" Rainbow Bridge sound as anything I've ever heard short of a real Uni-Vibe. Point is, I got the ModFactor so I could have the Uni-VIbe and Leslie and Flanger all in one box but that's not going to happen.
I basically bought the ModFactor because Evan said in an email when I asked if it could do the Uni-Vibe that I could tweak the heck out of the knobs and get pretty much any modulation type sound I want but that's not true in regards to getting a Uni-Vibe sound becaue of the max 2 phaser vs 4 phaser difference. However, I must say that some of the other effects are so amazing that it's still worth the $400 I shelled out for it especially because of how realistic the Leslie and Chorus sounds. You could spend $400 on a Hughes & Ketner Tube Rotosphere and only have the one rotary effect albeit the best on the market in a BIG stompbox, I ike having the Chorus and Flange etc..
[The Flanger sounds good but does not do even a close approximation of a Thru-Zero flange a'la Axis Bold As Love like the FoxRox ZTF (Zero Through Flanger) can do with flying colors]
UPDATE: I take this back! DanG told me that if you run mono input left and out to 2nd channel to amp you can get a negative through zero and it definitely works! It takes some tweaking and works best withteh expression pedal. I just write about the settings to get "Axis or House Burning Down" in another thread dated today. Dan is the man!
but the Eventide's Flanger patch does sound good with fuzz etc. kind of like a Boss BF-2. Since I already have a few Uni-Vibe clones and a Boss BF-2 it I pretty much use it for the Rotary and cool Vibrato patch on 8:2 to do songs like Electric Ladyland or Dolly Dagger and rarely for the Chorus 1:2 patch sounds good.
When you combine some of the efects with the TimeFactor the possibilities are near endless but yeah I still feel a bit dissatisfied that the Uni-vibe and Zero Through Flanger is not something this box can do unless they upgrade it's capabilities to being a 4 stage phaser and do something to thicken up the flanger and make it disappear and come back like Thru Zero is supposed to do. Because of the 4 stages vs 2 I don't see these updates happening anytime soon but perhaps they could tweak the flanger better and would be cool to have a patch like The Edge uses on Elevation where the chorus-delay effect trails off with a high pitched angelic synth like trailing overtone which I think I've heard on the Eventide Eclipse demo.