I did the exact same as you Charlie. After I made $15k on my first post, my instinct was to take it out immediately. I transfered about $3k out to Poloniex and converted to bitcoin. But within a few days of thinking about it I decided it made more sense to power up and invest in Steem as a speculation. I ended up transferring that $3k back in! I've since taken out a bit (for reasons I'll likely explain in a future post) but I am keeping almost everything in the platform.