Artificial Horizon – HELP!

It depends on what you want it for. If you're planning to do intentional
serious cloud flying, then you should be aware that none of the devices
you've mentioned is TSOed. Legal issues aside, I wouldn't put my life in
the hands of a device of which I don't exactly know how reliably it
performs.

If however you're just looking for a safety device, then probably all of
them will let you to keep the wings level. You could also consider to
buy a used T&B (the classic form, not a turn coordinator!). These speed
up reasonably fast, are extremely reliable and deal fine with any
attitude. You'd need some training, though, to be safe with a T&B.