High end PCs,,,,,in the wall or power conditioner?

Steuspeed,
Try Electro-Voice models that may require even more than 630Wpc(and can sound well if pumped hard!).

Plug them in the wall! You could buy one cord and run one amp in stereo. Probably would sound better.

630 Watts is overkill for just about any speaker.

You should run two dedicated lines, one for each amp and use 10 guage conductors doubled up for each hot, neutral and a single conductor is fine for the ground, along with 30 amp breakers, one on each amp. If you want to go a step further, pick up two PS Audio Ultimate Outlets high current model and plug each amp into them. I use two U/O high current with Classe Audio 25 amps running mono at 1600 watts per channel and they
sound better than plugging direct to wall with dedicated line. Happy Listening!

Two 600 watt mono's into ONE power conditioner? No way. Current draw will be constricted regardless of where you plug it in (20 amp, 30 amp...). A pair of P1200's may even be a little shy, and they cost a lot more than a few extra feet of power cord. IMO, plug 'em into the wall.

P.S.
Just adding to my last thought for chassis you can use a nice piece of granite from local monument shop that can shape it for your business needs(don't take any offence on this one as I'm poised to offence manufacturers and marketeers but not hm 'phools).

1. Wall dedicated 30A circuit(can be used for both monos) with built-in isolation transformer for surge protection.
2. Probably your budget won't need to be stretched further since the largest part is already taken care of. If you feel that you need a higher gauge for the powercords you can get Home Depot $0.50...0.70/ft wires braide and tight them and hook them up with high quality hospital grade plugs. The reactance @power AC freequency and so as skin effect changes zero to nothing in power transfer thus you're only interested in larger conductance and possibly less stiffness as thick wires can be very stiff and may require "extra space".
3. I was "brave" to strip my own Mainstreem Hybrid powercord after nearly 1 year of usage and compare with the older Home Depot wire and realized how foolish and naive was I about ANY todays manufactured PCs. Mainstreem Hybrid INTERNALLY started to oxide!!! Where is an advertized OFC cooper huh??? I can e-mail you that picture if you will contact me.
4. And the last. I found website that realy can help you professionally(as I can also relate myself to a specialist) to setup your power environment safe quiet and inexpencive and with quality far greater than audio-graded mega-priced brands.
Now I can "wisper" you to go there: http://www.elect-spec-transformer.com/product.htm, get a professional and budget advice, order their products and services for your audio power needs, re-box their outlettes with some extra nice chasis and re-sell them 5x the paid price here to audio-phools!