The Canon Vixia HG20 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 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's only a few spec variations between the flash-based HF11 and the HG20. The obvious is the HG20's 60GB hard drive versus the HF11's 32GB internal memory. In recording time, it's 5 hours and 30 minutes to 2 hours and 55 minutes at 24Mbps (and both can be supplemented with SDHC cards). Ironically, there's more differentiation between HG20 and its brother, the HG21: in addition to a larger 120GB hard drive, the HG21 offers an eye-level viewfinder.
Aside from capacity, it's really just a matter of size and weight separating the HG20 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 HG20'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 HG20, 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 smallish 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.