Same here. It was an amazing experience. I was lucky on my visit day and time that it was sunny and the sun was setting down which made spectacles of light show inside. I just stood in the middle for half an hour amazed.
The difference light quality makes to the experience is remarkable, and I implore anyone that visits to ensure you go at the right times on a clear sunny day.
You may think you've seen well lit stained glass before, but it's like freaking lazer beams of thick light penetrating the environment to the point where it doesn't seem natural.