My wireless SB2 has never had a drop out. A lot of things can affect wireless in your home: distance from router to SB, cordless phones, construction of house, proximity to a microwave, manufacturer of router, proximity to other wireless networks (apartment complexes).
My SB2 is about 20 feet from my wireless router. I use a wifi friendly DECT 6.0 cordless phone and the kitchen is on the lower floor. I can see about 6 wifi routers in my housing subdivision, but I've had no problems with interference. My wifi router is a Belkin, with dual antennas, that is about three years old. I keep thinking about replacing it, but if it isnt broke then why fix it. One final note; I have 14 wireless devices in located throughout my home (laptops, Tivo's, SB's) and none of them have had any problems with dropouts.