Hi Ms.Z:
I don't know where online you've been looking, but almost everywhere I've looked, the Canon HF-R20 is selling around that same $280 price (Canon USA currently sells it on its website for $349).
[They also sell the HF20 factory-refurbished in either Silver, Black, or Red for $249 at Canon Direct: http://shop.usa.canon.com/webapp/wcs/stores/servlet/product_10051_10051_302514_-1 ].
Walmart & Target currently sell the Sony CX190 for $269.
I own both Sony & Canon camcorders, and both are very good brands. (Sony makes more models that are used by TV stations & networks than Canon, but Canon makes more pro-TV lenses.)
Personally, I don't think either one is that great, although you get 8Gb of internal memory with the Canon model (none in the Sony) and the Canon will hold 2 SD cards at the same time (just one with the Sony). The Sony has a longer optical zoom-factor (25x compared to Canon's 20x). But you should read a couple of reviews for each model and make your own decision:
CNet Review (May 2012) for the Sony CX190: http://reviews.cnet.com/digital-camcorders/sony-handycam-hdr-cx190/4505-6500_7-35128679.html (They didn't like the image quality, for the money. And they thought it felt "flimsy".)
CNet review {January 2011) for the Canon HF20: http://reviews.cnet.com/digital-camcorders/canon-vixia-hf-r20/4505-6500_7-34468433.html
hope this helps,
--Dennis C.