I've an elite volare with 5 settings.
I started off in setting 3 and was regularly hitting 25 mph or more - up to 30 mph with ease, it was a bit false, too easy! I've been up to setting 4 for a few weeks now and it's brought my speeds down to a more realistic level. I still tailor my gearing to suit the particular session - last night I was spinning in the little ring for an hour around 16 mph in a Z2 HR (up to about 125 max)
With a weak resistance you can cover loads of miles at high speed but in my opinion it's probably not the best option.