I have exactly that item, although I bought it at Gamestop. It's worked like a charm for me. Glad I got it. As you may already know, it's tough to predict whether component or HDMI will look better, so as Eusis says, it may not make a difference in what you see.
However! I bought mine because my new TV had 3 HDMI ports and 2 component ports, one of which could also accept composite. The only other thing I had that uses HDMI was my PS3, but I had a number of things that could plug into those precious component/composite ports. Buying this device essentially gave me another port on my TV, and that was totally worth it.
Here's a link to it on gamestop.com, where you can get it far cheaper than Amazon. It's not available through the website, but you can put in your zip code and see if a Gamestop or EB Games near you has one in stock. Their "in stock or not" checker has been pretty accurate for me whenever I've tried it.http://www.gamestop.com/Catalog/ProductDetails.aspx?product_id=69119