Finding a multifunction printer

I have several printers and scanners at home (one with feeder at office). But still unable to perform a lot scan, print and fax features. Because every piece of them are not good enough or just too old. I'm looking for just one good printer which can do nearly everything, except flying itself up to the moon.

Here are some requirements:

1. Print, scan and fax.
2. Connect via USB, Ethernet (wired or wireless, doesn't matter), and RJ-9 phone jacket.
3. Must be a laser, color or mono doesn't matter. I just hate ink-jet.
4. Can manage scan and fax over the network (without using the USB).
5. Compact size (less than 45cm x 45cm x 45cm). Weight less than 15KG (not quite important)
6. Less than HK$2500 (mono laser) or HK$3500 (color laser)
7. Support both Windows XP/Vista/7 and Mac OS X.

Here are some candidates:

1. Brother MFC 7840N ($2588), as low as $2400. Mono laser
2. Samsung CLX-3175FN ($3499), as low as $2688(?). Color laser
3. Samsung CLX-3185FN, as low as $3150. Color laser
4. Fuji Xerox Work Centre 3119/3210/3220
5. Fuji Xerox Phaser 3100MFP/3200MFP
6. Samsung SCX-4828FN
7. Samsung CLX-3175FW/3185FW (wireless version of #2 & #3 above)

Seems none of my friends know well in this aspect. Still in search of a good one with a good price.