Hi,
I think you may want to have the mods move your question to the American Express Membership Rewards Forum. Over there, you will get lots of answers and opinions from knowledgeable FTers.

With regard to your question, I personally usually only transfer MR points on an 'as needed' basis. We first check with the airline by phone or online if the award seat we want/need is available and only then do I transfer points to make the booking. MR points never expire, so I don't transfer them until needed I hate to have them stuck in some mileage program I may or may not end up using.