In the v3 wardrobe, I can switch on 'show locked styles that you haven't currently earned' and then add them to my HA as normal. I hope I haven't missed some kind of massive all-encompassing free hair unlock (that would be embarrassing). As you can see, my HA is currently displaying Ramn which I don't ever remember unlocking, and does not show as unlocked in the wardrobe (but I am still able to click PREVIEW or Salon, and add it through Salon).

This works in both Firefox version 43.0.4 and Chrome Version 47.0.2526.111. In Firefox I am running noscript v2.9.0.2, but allowing all scripts doesn't seem to affect anything.

Yep, I can do it too. I tried using anew, and lo and behold i can, despite it not being unlocked and I have yet to buy this wig.

this is gonna be a problem.

Eyup. You can barely see it at the moment but I'm wearing the Delish Cees wig from the salon. ( Edit: its not showing in the forums but I can definitely see it on my sidebar. :s ) Steps I took to do it: Hair tab. Have "Show locked styles that you haven't currently earned", from "no" to "Yes"
Scroll down to a hair style that isn't normally available to you, select 'Salon" Add to avatar, and save.

It actually does let me save it and wear it, but upon entering the Wardrobe again it seems to disappear from my avatar, and I think if I save over it with it not appearing it'll disappear (Havent tested that.) but I really shouldn't have been able to save it and wear it to begin with.

You're welcome! glad I could help :D ( and now it's showing up on my avatar on the forums, so yep it definitely stayed put once saved. should I leave it be or should I go ahead and remove it ? )