I think they had better success integrating hardware companies, but SA — which was pretty much a hardware company — was a pretty big counter-example. I’d also argue the further they strayed from their core market, the worse the results. See also: Flip and Linksys.
I worked for NDS when they were acquired by Cisco. They've spat them back out a few years ago. Not entirely sure Cisco should have got into the video space.
I enjoyed Cisco (great 4th July parties!) but it never felt like we were properly integrated.