Every time I try to form a coherent opinion of the Sony NEX-VG10 camcorder, I end up circling back to, "Well, it's the first try." On one hand, it delivers the flexibility of interchangeable lenses in a traditional run-and-gun design at a relatively inexpensive price for the pro user. On the other, the design falls short for the run-and-gun crowd, and it lacks some of the features that someone paying $2,000 for a camcorder wants, most notably progressive recording. If Sony sold it with a different lens, or body only, the price would be far lower and it might be more attractive to the prosumer crowd it seems to have been designed for. In other words, while it looks like a pro camcorder, and costs as much as one, it acts like a consumer model.
For example, the video looks good, but not great. It renders accurate colors and consistent exposures, with solid dynamic range--the contrast looks very good, without unusual clipping in highlights and shadows, even in harsh sunlight. But there's also wobble, moiré, and a muddiness in midrange-distance details like grass and leaves that I don't expect in a camcorder in its price class. That's partly due to the lack of a progressive recording mode--though it captures 30fps, it records at 60i, introducing all the aliasing issues that interlacing does (this is a drawback of standard AVCHD). The cheaper's video looks better, and as far as I can tell makes more of the 24Mbps bit rate than the Sony.
The 18-200mm kit lens uses the same optical stabilization technology as Sony's camcorder optical SteadyShot (including Active mode). Like the other NEX lenses, it uses electromagnetic iris and focus activation in order to remain silent while recording. It's quite good. It can autofocus closely and decisively, even in low light, although the lens/camcorder combination doesn't always accurately guess the subject. It exhibits very little fringing, and the nice, round aperture produces attractive out-of-focus highlights.
But while it's solidly constructed (and heavy), with a nice feel for manual focus, the lens is hard to zoom smoothly and precisely; it's stiffer zooming in than out. It can get kind of unwieldy, and you'll probably have to shell out for a good follow focus (or DIY).
The huge, rather funky-looking stereo microphone consists of four omnidirectional mic capsules that Sony algorithmically clumps to create a more unidirectional, cardioid effect. It's too bad that you'll want or need to cover it up with the bundled dead kitten (those rather unsavorily named and frumpy-looking puffs that you put over the mic as a noise shield). It produces very good sound--subject to the camcorder's limitations.