I read white paper but not always, I follow ICO review expert and research on the project team of professionals.
Me too. To be honest, I don't read wite paper so often. I think almost all of them are promising. I folow the opinion of my experts. The best of them is my good friend in the team who feels nice projects 
Let's be honest that reading the whitepaper is too boring and I swear some here are like " yeah I read it " but when you see the almost a hundred pages of it you'll get too lazy to read it. Yeah I read the WP but just the important part like the roadmap like their mission and goals. Also the partnership is a must check but sometimes I ask the dev if they have the summary of their WP.