Hi Coffeegirl,
I've had ENG testing done, and you won't find it uncomfortable. I don't think the ENG testing has changed much even though I had it done years ago.

They might pour cold water in your ears, and you might feel dizzy during parts of the test, but they are testing to see what brings on vertigo if you have that symptom.

For me the ENG was part of the MS diagnostic procedure but I was diagnosed with MS before there were any MRIs. Nowadays they rely on the MRIs mainly, I think.

Vertigo is sometimes a symptom of MS but it can also be due to quite a number of other causes.