Worth upgrading to the Ninja?

Currently I have the Zalman 120mm led copper heatsink on my cpu.

Temps are around 39C idle 49C load. Would it be worth getting the ninja? What kind of temps could I expect? My cpu is the Pentium D 820. Does motherboard make any difference in temps?

Your temps seem fine now but if you start to push the envelope then the Ninja would be alot better.