I share wireless signal from my neighbor's router, I have an old linkSys WUSB11 works ok for years, usually I get two bars on signal strength. Bought a new PC with Windows 7, also need a new adapter which supports Windows 7, I bought a LinkSys WUSB100 because it is a name brand and my previous LinkSys WUSB11 works ok. Not quite, the WUSB100 only get one bar and some times two bars on signal strength. Switched to NetGear WP111, this one works better than the WUSB100, but just marginally better. Based on Amazon reviews, try this Alfa adapter, installed the drive, connected the signal, immediately I got three bars on signal strength, it does work better than other adapters. Only one thing is, the one I bought came with the original antenna and a 15 inches 9db antenna, the 9db antenna make no different and actually worst.
Update, 9/29/2010, I saw reviews on the AWUS036H (1000mw) which is lower end model than this one. Many people claim it works better. So I give it a try, yes, it is absolute better, I got 5 bars instead 2-3 bars, the cheaper lower end model did work better. Don't waste your money just go get the AWUS036H instead, don't border to get the 9db antenna too.