Upload & Sell: Off
If the objective of the 25 post is to stop scammers why not also limit the number of posts a new person can make per day?
It seems like because I wanted to buy some lenses I need to post opinions where I didn't always feel they were relevant.
Disabling posting to sell made a lot of sense to me, disabling buy and PMs for sub-25 posters does encourage gaming of the system even where someone has legitimate motive.
2 cents from the obvious newb. There is probably another thread already hashing through this very stream of thought.