We had a tour guide called Fraze (I may have spelt it wrong). He was simply amazing, and had all the knowledge in the world about Taj Mahal - he had great answers to all our questions and even took professional pictures for us (I do love taking self-portrait pictures). He was not persistent when it came to the Marble shop as he'd wait outside until we were finished (I say this as other tour guides would be persistent in order for us to purchase an item). I had a sense of care when we were with him and you can tell he loves working as a tour guide.
I'll definitely recommend Fraze if you are looking for a day trip to the Taj Mahal.