If I am right in assuming that you are part of the larger Bouygues group, of which one part is currently involved in the Batersea development then you have a very good person to speak to already in your company.
The BIM manager for Batersea at Bouygues spent a lot of time and effort investigating various laser scanners on the market for his previous company and I am sure would be happy to help you out if it is appropriate. Let me know and I can PM his name to you.
On here you will always get a biased view, whether from a vendor directly or a long term customer of a particular vendor. The best way to discover what works for you is to undertake your own investigation and get demos of various bits of kit and software to find what works at the right budget.
Good luck and happy scanning