I have been going since it opened about 10 years ago.
I have never had anything stolen. (I put a chain through my spares and don't leave stuff out)
I have never had any problems with cops doing drunk tests. ( I don't drink and drive - duh)
I prefer Evarts because it's close to town to get food etc. There are many more trails on the Evarts side. The trails to Putney suck if you are broken and try to limp back to camp (steep, slick, and narrow). Putney has a much nicer campground. Rent a house in Evarts is the best way to go. Avoid the cabins behind the gas station unless you want to stay in a small shed, lol.
Yes 3-4 days it perfect. Try to go with a group or get a guide so you won't miss the best parts.