Hilton HHonors - Award vs. Paid Stay....Cost Ratio

We are working on travel plans to Budapest Hilton(Cat 3)...Prague Hilton(Cat 3)....Munich Park Hilton(Cat 4) in Early November. Two nights in each hotel. I have not used points for any award stays before. I enough points (80. 000)for 3 nights. I am not sure if I should buy more?
My question is what value system should I use. I want to know the value system, you great members in this forum use. I.e 1000 points is worth?

Second part would be the Class of hotel, how does this change the values. As I am looking at a Cat. 3 and Cat 4 for my travel. I am going to be Diamond upon the time of travel

Costs Budapest (Cat 3) $163/ Night (Danube View $40 extra)

Prague (Cat 3) $176/ Night

Munich Park (Cat 4) $176/ Night

Thanks All

From last month:
http://www.flyertalk.com/forum/showthread.php?t=434519&highlight=point+worth

And:
http://www.flyertalk.com/forum/showthread.php?t=359619&highlight=point+worth
http://www.flyertalk.com/forum/showthread.php?t=356310&highlight=point+worth
http://www.flyertalk.com/forum/showthread.php?t=131395&highlight=point+worth

One Suggestion: With a reward stay your reservation will be for a standard room type. Upgrades for HHonors status may be given, however, if the view of the Danube is important to you I would reserve that as a paid stay.

Others more familiar with that particular hotel may give you pointers on how they treat Diamonds there. Or if "Upgrade Me" searches for you again maybe he'll post links for you.