Both have become the top two players in a vast and growing market...and they are buying every small player in town. Not only is their core business solid and growth oriented but they grow by acquisition, which allows them greater market share.

Their 5 year charts show where all should have been during the post-bubble/bear market.

PDCO

http://bigcharts.marketwatch.com/quickchart/quickchart.asp?symb=pdco&sid=0&o_symb=pdco&freq=2&time=12&x=26&y=15

HSIC

http://aolsvc.pf.aol.com/us/quotes/charts?dr=60&sym=HSIC&exch=USA&state=default&x=13&y=5