Fyi,

Both cams are of different categories.

DV300U:
Model GY-DV300U (aka Streamcorder)
3 x 1/3" CCDs, 440K pixels
Professional Division

DV3000U:
Model GR-DV3000U (aka F1.2 SuperBright lens)
1 x 1/3.6" CCD, 1.33 Megapixels
Consumer Division

True. JVC does very confusing things with numbers and letters. There's also the GY5000 and the DV5000 (or something like that--I never can keep their letters organized in my head). One is a 3 chip 1/2 "chip camera, and the other is a single chip consumer camera.