After hearing of the long connections between the airport and Bentota I opted for the air taxi. family of 4 cost 350GBP but money well spent.
Arrived from LHR @ 13.30, met at arrivals and escorted through customs etc. Waited in business lounge until flight @15.30. taken to sea plane (only 4 of us on board), 25 min flight, great views, then landed on bentota lagoon. Taxi to Taj, having a beer by pool @ 16.15. Trip so good I booked for the return.
Used a local driver called Bundi for trips, very safe, knowledgable and gave great value. I have his numbner if anyone wants it.