Has anyone tried the above deal advertised here?

They say you will get the free boiler if you switch over from electric or oil and will also install an above or below ground gas tank as well. If you have used it, were there any problems or hidden charges etc? Can the free boiler run up to 8 radiators? Are they combi-boilers? Would you recommend it?

Would be interested to hear from you if you have done it?

Thanks for reading.