Finding a control within a page

Hi,
Just wondering.  I have 2 user controls - both independent of one another, however both show the same data in slightly different ways.  So when control 1 is updated, control 2 needs updating and vice versa.  This is easy to do, I just find the user control and call the updatepanel to refresh it.
 
At the moment the method to find the control is fairly rigid because it is has fairly limited use, like this:
page.master.master.findcontrol(a).findcontrol(b).fincontrol(c)
I have a piece of code that allows me to find a control on a page, but would this be an expensive option as it traverses all the page controls?  Looking for advice.
 
Also if there is a better way of making one control update another, I'd be happy to take some advice.
 
Thanks
 
John
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