pumps (for beckett)... pressure rated vs non, head pressure?

[smokinreefer]

thanks for all the input guys...
this is all still in the planning stages for me, cuz as i mentioned my tank downgrade/upgrade is still up in the air, and lighting change, skimmer change, its all driving me nuts!

but at least now i have an idea as to how these becketts work and whats needed to run them!

so it looks like i'll have to sacrifice a little noise and go with a Mak4. now what about the Iwaki's? i understand they are a higher quality pump, but are they qiueter than the Mak4? cuz the price is pretty much double!

thanks again.