While it's true there are some pretty awful tutors from India, with a bit of care and diligence British parents can locate excellent and experienced online 11+ tutors from India for teaching mathematics and the sciences, and save a bundle in the process.
While we can't speak for most other tutors from India, for ourselves we have seen that INDIAMATHS.COM tutors are native English speakers, educated in the Cambridge systems, possess at least a masters or Ph.D in mathematics, engineering or science, have decades of teaching experience teaching international students for Cambridge, Edexcel, AQA, IB exams and are up-to-date with the current syllabus and textbooks for these exams.