I have the permanent tag on all of my MVs. I've only been stopped once, and explained I was coming home from a Rally thinking they might gig me on the limited use. The Deputy said he didn't care about the limited use restriction, he just wanted to see I had a tag since it is not displayed. He was cool and after checking the tag let me go.
I drive all of my MVs regularly and other than the one time, have not gotten a second look. Use good judgment. I wouldn't drive it to work everyday.