I blundered across an interesting article in Antenna Systems and Technology magazine (Nov/Dec 2005, and yes, I'm behind on my magazine pile reading).
Why MIMO Matters
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compares the performance of Linksys (Airgo) SRX MIMO WRT54GX and WPC54GX verus Netgear RangeMax beam switching (Video54) WPN824 and WPN511. Unfortunately, there's no comparison with a beam forming product.It's quite an interesting read and method of testing (using a laptop on a turntable). One item that caught my attention was that the Linksys combination allegedly still ran at 5Mbits/sec thruput, going a distance of 206.5ft, through *FIVE* walls (ceiling and floors). I don't believe it, but it may be possible.
Some related stuff by the same author/company at:
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Video54:
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