PSU- last component in my new build

As the title says I'm one PSU away from firing up my new box.
Any suggestions will be much appreciated.

CPU- E8500 E0 step(overclock to around 4GHz)
CPU cooler- Xigmatek red scorpion s1283
Mobo- gigabyte GA-X48-ds5
Ram- OCZ Reaper pc8500 2x2gb kit
GPU- Palit HD4870 Sonic 1gb (With provision to run 2 of these in crossfire)
Case- Antec 900-2
HD's- 2x 640g WD's in raid 0, 2x 120gb seagate, 2x 1tb Samsung (or similar to be added)
Running on a 28inch viewsonic, native resolution 1920x1200

I'm an electrcal fitter by trade so not completely in the dark over this decision.
I'm also in Australia in hot conditions, so I don't want to push the GPU to hard.
Modular would be a bonus because of Case size I think, but of course not absolutely necessary.

I'm sure there is a PSU that will suit me perfectly, but I'm getting stuck with all the reviews I've been reading and can find pros and cons with everything.
Hence I hope I can get some direction to make a decision more quickly.

Cheers
Chris

budget would be around the $240aus mark.
http://www.shopbot.com.au/csf/AU_i [...] lay0.html]
This site gives pretty much the options that I have at this stage.Ones I have looked at are:
Antec EarthWatts 750W ATX Power Supply
Xigmatek NRP-MC 750W 80+ Modular PSU
Seasonic M12-700
Corsair TX-750 750W(but it's not modular)
OCZ GameXStream OCZ850GXSSLI - 850W
Several silverstones aroung the same size but newegg reviews have them failing some of the time.

Well the Seasonic is $210 delivered which seems to be good value.
Will it be pushing to hard to run my crossfire setup later though?

700-800w is more than enough for that rig, you could get away with the Corsair620 (modular) quite easily

I run a similar rig on a corsair HX520 (see below), the 620 should be fine. Might not be enough for XF but will cope fine with more RAM and a quad.

My system:
OCd Q6600 (3.2GHz)
4x1GB RAM
HD4870.

Those 3 are basicall all the same
The Corsair 620 is a Seasonic OEM and both are great.
The 750 is CWT and also great.
Any which is best bang for ur buck is best

corsair have not been doing PSU's for that long, which means its probably a brought in re-badged unit, I think seasonic manufacture them, or if not they have been sticking badges on for a lot longer than corsair have

Main companies we kno of as consumer products are almost always re-badged OEMs....
People like Sirtec, Topower, Seasonic, Channel Well Tech (CWT), Andyson, Enhance, etc. generally make more "business" and server oriented stuff

Then companies like OCZ (Sirtec), Corsair (Seasonic + CWT), Thermaltake Toughpower (CWT), PC Power (Seasonic), Tagan (Topower) and Ultra X3 (Andyson) (just some examples) use those designs and might do some changes specific parts. Corsair puts the luxury of 105C caps vs. Seasonic (not a big change cause Seasonic is great otherwise). While say someone like Xigmatek (decent CWT OEM) uses some lesser capacitors in their CWT builds to cut some prices