There is a substantial performance difference in SSL handshake speed and site performance if you have a central server, vs multi-edge storage before you get to Cloudflare. The closer your edges are to Cloudflare's edges when the handshake happens the faster things go. The handshake delay is particularly slow internationally with Heroku running under CF, since you can't predict what heroku IP you are fetching from, unless you fix to one point and then latencies are still long at far away locations.