Stick to one and hopefully to the one that is the leader, you can actually verify which one it is ( http://www.similarweb.com/website/angel.co?competitors=gust.com ). Fundraising consumes time, you could be at it 1 month 6 months or even a year so I recommend sticking to one single platform. It tends to be chaotic once you are 2 months in the process and you need to update multiple platforms, eventually one is going to lag behind because you will be so inmmerse in other activities. Also from a SEO perspective your top listing will benefit more when content is not replicated in other platforms, that way you dont dillute yourself and the power of achieving rankings for "long tail"

As of today more investors "gravitate" today in Angel List than in other platforms.