Ultra 120 Extreme or alternative

I am looking for a hsf to cool an Q9450 (on Asus P5Q-Deluxe). Thermalright Ultra 120 Extreme seems to be the best. I will get it if it is really necessary. I say 'really necessary' because I plan only to mildly overclock to 3.2GHz-ish. So, is it necessary to get this montrosity (size and weight) to do my job?

If yes, please suggest a couple fans. Also, should I expect installation complication to mount it on a P5Q-Deluxe?

If no, please suggest one or two alternatives (I desire one which blows air horizontally). I wonder if Ultima 90 is ok? Does it go well with P5Q-Deluxe?

Appreciate any input.

To be honest the stock should be fine, so any heatsink would be ok. You would likely be able to get 4ghz stable if you ran with a 120 though (possibly more).