I don't know about MT Gold, but I used CodeQuick, and am extremely satisfied with it. I got to 5wpm in about 3 weeks, and was up to 7wpm by test time (2 weeks later). I am now up to 12wpm, which is about 3 months since I started, and I'm not as diligent about practice recently.
As far as the test goes, they had headphones for us, as the test was in the same room as the written. I guess each test is different. I'd suggest bringing a set of headphones, and if you're the only one there, they'll probably let you use them. I'm a VE, and under those circumstances I'd let you.