The Canon Vixia HG21 is an excellent HD camcorder that's reasonably easy to operate out of the box and looks good, too. It's almost identical to the company's Vixia HF11, but rather than recording mainly to internal flash memory, it records to a hard drive. As for performance, it's as good if not better than the Sony Handycam HDR-SR11. So in the end, it comes down to a preference for flash memory or a hard-disk drive as your storage medium of choice. And if it's for flash, your willingness to pay extra for it.
In addition to the price differential--which varies quite a bit on the Web, so it pays to shop around--there are only a few spec variations between the flash-based HF11 and the HG21. The obvious is the HG21's 120GB hard drive versus the HF11's 32GB internal memory. In recording time, it's 11 hours and 5 minutes to 2 hours and 55 minutes at 24Mbps (and both can be supplemented with SDHC cards). The HG21 also offers an eye-level viewfinder, which is more and more of a rarity.
Aside from capacity, it's really just a matter of size and weight separating the HG21 and HF11; the HF11 is smaller and lighter at 2.9 inches wide by 2.5 inches high by 5.1 inches deep and 15.1 ounces to the HG21's dimensions of 3.1 inches wide by 3 inches high by 5.4 inches deep and 17.6 ounces. Positions for controls and I/O jacks are slightly altered between the two as well. Most notably, the dial to switch from video/still record to video/still playback is on the back for the HG21, and is on the side for the HF11. However, regardless of the model, the controls are large and easy to operate.
A five-way joystick and Function button--which navigates frequently needed shooting settings--live on the bezel of the camcorder's 2.7-inch LCD. Putting the controls out on the LCD instead of under the thumb can make it difficult to simultaneously change settings and keep the camcorder steady. In addition, manually focusing with the joystick can be a pain, regardless of the zoom-view focus assist.
The HG21 records AVCHD video at a maximum bit rate of 24Mbps, and can hold up to 45 hours, 15 minutes of video at the lowest bit rate of 5Mbps. (There are five quality settings in all, which I find excessive.) That higher bit rate goes to support the full 1,920x1,080 capture, the norm for most new models, compared with 1,440x1,080 for older AVCHD camcorders, which required only a 12Mbps maximum bit rate. You can record best quality movies to SDHC cards as long as it's a Class 4 or better (Class 6 is currently fastest).
Its optically stabilized f1.8-3.0 12x zoom lens has a longer reach than the typical 10x lens available in this class, but the rest of its features are fairly common in Canon's prosumer models. For video, these include aperture- and shutter-priority exposure modes, 3 fixed/1 variable zoom speed options, a video light, Instant AF, and a wind-screen filter. You can also record in progressive 30 or 24 frames per second modes, as well as 60i. For still photos, metering, flash, and burst and exposure bracketing, options become available as well. The camcorder also supplies a complete set of ports and connectors: component or mini-HDMI out for direct-to-TV playback, mini headphone and mic jacks, and USB for downloading to computer.