Regarding the wheel nuts, if you crank down on the Hiro Seiko wheel nuts on a new rim, it can be very difficult to get them loose the first time you go to take the wheel off. Every time after that they should be easier, but still takes a little effort. I've never had an issue with Hiro Seiko wheel nuts, they are very good.
I have some of the Avid Triad wheel nuts on the way that I'll likely use at Snowbirds. I've heard good things about them and I'm really looking forward to using them.
I would avoid the non-flanged nuts as posted in the link to the A-Main site. Non-flanged nuts will allow the wheel to flex more and potentially bend or break. That little bit of flange does a much better job of preventing that.