I would say with my (hopefully short) experience that it depends how bad your father is.
Should his state be critical, just go for it. German are more serious people than a lot of the other barbarian's around.

The drawback is that it is new. And that Xcell treated 11 people so far (according to the recent update on their web site). So really, waiting a couple of year's for long term proven effects can't be bad.

The pro's though is that according to a belgian scientist recent discovery, the process of differenciating dopamine cell's seems easier than expected, nearly natural

In a nutshell, should I already be in a critical state, I would go for it straight away.

In the meantime, I'll try everything else.

I'll try permanent acupuncture implant on the 18th of november.
Traditional acupuncture has a great but a bit temporary effect.
Really eager to try the implant.

I'll let you know of the outcome, but please don't hesitate to remind me if I forget.

Good luck for your dad.

Damsee