Membership Rewards points are great for airline miles redemptions because you can wait until you need to book the flight, search all the partner airlines for availability, and then instantly transfer the points to be redeemed for a reward flight. This way you don't have all your miles in an airline that doesn't have availability when you need it.
An exception is when there are really good transfer bonuses.
Delta is currently running a promotion offering an extra 50% bonus Skymiles for all American Express Membership Rewards points transferred. As an added bonus, if you transfer 100k MR points, you will get 25,000 Medallion Qualifying Miles (MQM), or Medallion Status.
Here's an example: let's say you transfer 100k MR points to Delta - you will get 150k Delta Skymiles plus 25k MQM medallion points. This automatically upgrades you to Medallion Silver Status. Here are the following perks of Medallion status:
- Waived baggage fees
- Unlimited complimentary seat upgrades
- Complimentary companion seat upgrades
- Preferred seats
- Upgraded waitlist
- Priority check-in
- Priority boarding
- more at Delta Medallion
If you want to take advantage of this offer but don't have Membership Rewards points, I suggest taking a look at the American Express Platinum Card. Delta offer expires 09/30/2011.