i think the link was to the ASUS TOP CU i was suggesting, the numbers match
http://www.newegg.com/Product/Product.aspx?Item=N82E16814121393&nm_mc=AFC-C8Junction&cm_mmc=AFC-C8Junction-_-RSSDailyDeals-_-na-_-na&AID=10521304&PID=3463938&SID=
at 89.00 I'd imagine it'd be a decent 600 watt psu, but you never know, if you trust em I'd say you're probably good, most shops won't intentionally rip their customers off thats a bad way to get them to come back, i know i wouldn't do that to my customers. really the 450 can run on a low wattage psu it only uses 1 6 pin connector.
i was just warning that some psu manufacturers will just put a label on their sub par power supply like the link i showed where a company slapped a 580 watt sticker on a 200 watt psu.
it might be helpful to call the shop and ask what model and brand the psu is that they are putting in.
as for us as a community most people here are pretty nice and helpful when we're not squabbling on geeky stuff liek amd vs intel or ati (now also amd)vs nvidia then we just get our nerd rage out on each other