<a href="https://app.roll20.net/account/supporter" rel="nofollow">https://app.roll20.net/account/supporter</a> shows all the benefits. They are mostly geared toward GMs, so if your players also GM other games, it would be a benefit. The only benefits that directly apply to players are the Character Vault, which is a great boon if they like to keep copies of their characters at different levels or take them to other games, and the Tablet support (which they would get anyway if connecting to a subscriber's game).
