Is it better to upgrade to premium rather than to cash it out first?

It's up to the member to make the call if they want to cash out while on Standard, or decide to get a Premium then build up to the required cash-out for Premium ( which is $6, instead of $8 for Standard members ) along with the perks of that follows for Premium users

It'll be up to you, since it's your earnings -- you decide from here where would be best