All the companies you mentioned except for the "powers" I've heard good things about. I just recieved my computer Monday-I went with DigitalStorm. For price/quality I was debating between Vigor and DigitalStorm but after reading the forums on DigitalStorm and reading their resellerratings I leaned towards DS.
I personally am very happy with the build I ordered and everything was great. Thats the absolute main reason I went with DS is their customer service is great. I like the replies they give to people with a bad experiance, and every question I asked on their website was answered within minutes. Also the fact that they will build whatever system you want-even order parts they dont carry speaks volumes to me.
In any case good luck with your search. It looks like you're on the right track as all the builders you mentioned have good reputations. For me the choice was between Vigor and DigitalStorm but for the money and personal service I went with DS and have no regrets. Couldnt be happier with build and knowing they will be in business for some time is comforting. I'll actually be adding my review for DigitalStorm within the next week-just breaking her in now.