Unions, for or against?

I don't think we have had any sort of conversation on this blog regarding unions. I'm not entirely convinced that they are indeed a good thing. I suspect this is due to never ending propaganda that permeates the media regarding unions. My intuition tells me that unions are in fact generally good and very much needed. The media always tells me that some union is on strike and that is the cause of a work stoppage or slowdown. They never really present the flip side of that coin in which some corporation is refusing to treat it's employees fairly and THAT is the cause of a work stoppage or slowdown. I don't have any personal experience with unions so I can only base my opinions of them through anecdotal evidence given to me by friends who are involved with a union. One such friend had previously worked for the state on two separate occasions and generally had a good experience with both jobs. He has since left those jobs and moved on to a unionised job where he has much better health care, much better vacation time, much better sick time, a much improved retirement plan and brings in more than twice as much money as the two previous jobs combined(the work is not significantly more difficult nor complex now). That tells me that unions are pretty damned good to be involved with. Of course he does have to pay union dues, there is no option for not joining, it is compulsory, but the amount of money that he now makes dwarfs that piddly union due into obscurity. The company that he now works for is also very successful, a Fortune500 company, and seems to be doing reasonably well even in our current economy. So with all that said, can anyone give me a reasonable argument for why unions are actually bad for people and business? And no a video like the following does not convince me.

Which brings me to this Americans Are Raring for a Fight Against Corporate Power which I found at Alternet. The article discusses the EFCA, Employee Free Choice Act, and how that law would make it much easier for labor to organise and stiffens the penalties for those companies who would try and stifle labor organisation. Are we really ready to re-embrace unionisation in America, and if so is that a good thing? I think it is.