I'm currently looking into buying some aero bars for my bike, but most of the bars I'm looking at seem to just clip onto the handlebars I already have. So, are they secure, will they support my weight?

These are the bars I was thinking of getting: http://www.amazon.co.uk/Tranz-X-Tri-...=ISSCIR1QWMQES Are they worth it, or do I need to save up and splash out a little bit more?

Thanks guys.