We went to Mumbai with P&O in 2012. It is a great place to go and worth the visa fees
I don't know where you live but we went in person to the visa office in Hayes for ours which cut the cost considerably. It cost around £45 per person (may be a bit more now). The application had to be filled in on line which was straightforward and all was waiting at the office. The service was very friendly and very efficient. Had to go back to collect passport with visa in a couple of days later.
I am sure there are other offices around the country that you can go to if Hayes is too f