Tiltable lens adapters

[petrochemist]

I've recently seen loads of tiltable lens adapters on e-bay for mirrorless cameras.
Has anyone tried one, and are they any good??

Proper tilt/shift lenses are far more than I can justify (~£1000+) but these adapters seem cheap enough to mount my existing PK lenses to micro 4/3 or Sony NEX, even if I have to get a used camera to go with it (~£150 for both).

I've tried the DIY approach to tilt lenses, with an enlarger lens which works, but has major drawbacks.

If anyone has experience of these adapters I'd love to hear the pro's and cons!