I've read a lot on these forums but haven't seen anything from people who've used and could compare the various low-end pre-made DOF adapters out there.
All I can go by is the videos on vimeo and those posted here, but it seems to me that they all have their limitations:
GT35: seems to need more light than other models
Handy: pricey, cumbersome, fixed mount and orientation
Granted, the vignetting in the Jag and Twoneil is reduced in the higher end pro and plus models, but it's still apparent. It actually looks good in many of the test shots, since they are not narrative and short (and typically exteriors, which are brighter), so it's like an effect, rather than a limitation. These would make awesome Hallmark commercials. In a narrative or longer piece, though, I'm afraid this would become tiresome at best.
I'm leaning toward the GT, since its samples seem to have the best edge-to edge look, but it seems to require a lot of light, moreso than the other models. It's hard to tell since the samples are under varying conditions, but it's one defect I see that's common (lighting, either over- or under-) in the GT sample interior shots. This may be due to what appears to be a longer body, or simply poor lighting, but I don't know.
In any case, I'm wondering if anyone's used these side-by-side for a comparison, or even months apart with similar lens and camera. If you were unhappy with one, then found another more to your liking and why.
Ultimately, I do understand these are all budget models, so I can't expect too much. I also wouldn't be surprised if you said they are pretty much all the same, except for design (noise, appearance), since they all likely use similar quality components.
If you don't feel comfortable posting in the thread I'd appreciate it if you PM me.