I have now completed my application, and I want to extend my thanks for your superb proofreading service. … I have worked with various proofreaders on my academic and website projects. However, your professionalism and attention to detail can be considered a benchmark.
I was particularly impressed with your level of detail. The fact that you went the extra mile to cross-check the dates of conferences mentioned in the personal statement was impressive. Occasionally, I have writing pieces that require proofreading. I would be more than happy to continue working with you in the future.
Thank you once again for your exceptional service.