The WA Keyword tool works well also and I am glad you like it. I use it as well. The reason I prefer Jaaxy is because it is an entire suite of tools in one package for an affordable price. Good choice to wait until you can budget for it. The free version gives a good taste of what is available but the paid versions both Pro and Enterprise are truly game changers. Once you make the leap you wont go back.
Of all the tools listed in this article, Moz Link explorer is an old one & quite popular. If you want to compare backlinks between two or more domains, Open Site Explorer is worth trying. This tool works best when you have a paid account of SEOMOZ though a free version of this tool is good enough to get you started checking the backlinks of your site and the sites of your competitors.