American Express is offering a 50% bonus on transfers from Membership Rewards to Virgin America Elevate through March 10. American Express hasn’t offered a 50% transfer bonus since November 2012.
My rule of thumb is that Virgin America’s points are deflated, that one Virgin America point is worth about 2 points in a European airline frequent flyer program. You can use the points for about 2.2 cents apiece towards travel on Virgin America, or for fixed-point redemptions on their partners. Their points are reasonably good for redeeming on partners (with fuel surcharges).