I think to state that all Indian SEO Companies are experts in their field is an enormous and misguided generalisation. There are good and bad SEO service providers in any country. Personally I feel the extra benefit you get from employing an SEO expert within the target market country is wide ranging. Compared with a foreign company a company operating in the UK is likely to have a better grasp of the English language, more experience of UK consumer habits and a knowledge of UK directories and the general 'zeitgeist' of the time. In International Marketing the importance of local knowledge is widely accepted. On many occasions companies have come unstuck when entering a knew international market because they did not understand the local marketing environment properly. So in summary, you should always employ an optimiser who is based in the target country for your products or services.