i used to have the virtuals in my strat. 54s (n/m), heavy blues (b). they are real quiet.
the heavy blues in the bridge is higher in output, a bit thicker sounding but still retains the strat "twang", if there is such a thing. the 54s in the neck and middle is very "transparent" sounding. i can't say it is glassy, coz it is way too smooth... the in-between sound with n+m "approximate" the fender tone, but the m+b isn't that good.
i've got nothing bad to say abt them, but i switched my p/us back to the original fender ones as i feel it is not really a strat "sound". i guess when u loose the noise/hum, u loose some tone/character too. mayb just my ears...
lots of ppl swear by Kinmans if u wan noiseless vintage tones. never get to try them tho...