Yes, I had both these tests done recently. I had my tumor removed in 2005 and still struggled with headaches, dizziness (even though I had vestibular rehab), my field of vision bounced (like a bad video) when I would walk around, my contralateral ear was giving me trouble with fullness, popping, heartbeat-like noise, pressure changes and level of tone was coming and going. The doctors were suspecting Menioers Disease so ordered these tests. The test for ABR (Audio Brainstem Response) and ENG (electronystagmography) were not invasive, nor painful. During the ABR test I sat in a chair comfortably while techs attached electrodes to various areas above my eyes. They inserted in my ear another device that would emit cold, then warm, water then air. I do remember one part of the test being very noisy. But I also at this time, had the EcOG test too and maybe it was this test that was noisy. Anyway, it is another device small enough to fit into the canal that would make a loud noise, but didn't in anyway hurt. Important you stay calm and relaxed so they can get a good reading. The testing did make me dizzy, but not to great extremes and went away quickly. The ENG test was pretty much the same thing only this test I had special "goggles" on whereby the tech can see my eyes up close. It is totally dark while wearing these goggle and my body and head were positioned in different ways while they watched/recorded my eye movements. They also used the warm/cold water in my good ear. I was also asked to follow a little "dot" of light and stare at it in certain directions. This is to see if nystagmus (involuntary eye movements) is gaze induced.
I had my husband drive me, but in hindsight he really wasn't needed as I was no more dizzy nor nauseous than before testing. I hope this helps and am interested in finding out your experience. Relax during the testing as this will give the best test results. None of it hurts.