Without a doubt using mypoints for Hilton is a waste of money. You can redeem for a multitude of Gift Certs.

For example 1,400 MyPoints = $10 in gas

So a for instance is this:
10,000 Mypoints = 10,000 Hilton points
10,000 Mypoints = $70 in gas

It takes 30k Hilton Points to stay at a 200 a night hotel. If you were to spend the Mypoints on gas and buy the hotel room, you would earn hilton points for your stay.

Do even ask about exchanging hilton pts to airline miles...the value gets worse.
example
10,000 Mypoints = 10k Hilton = 2,000 AA

would you take $70 in gas or 2,000 AA miles ?
....easy answer there

My humble opinion.