In reply to glenn0010:
Ive done it and swiftly quit after very poor communication and a hell of a lot of petty dishonesty. I was a "mountaineering adventurer" and they decided to lump us with hikers and do via ferrata, still got to do VF but not what anyone signed up for and having both hikers and mountain based climbers made the group pace pretty hard to manage.
They had promised me paid flights from my nearest airport then booked me on to london stansted flights meaning it cost me £200 just on UK travel. When challenged, they outright denied this.
The only time i'd recommend doing this is if you're a london based boulderer as the guys i know who did that through NB seemed to actually get a good deal. They got to climb with and get coaching from Louis Parkinson on occasion.