I have an Innova, love it, but there are lots of good machines out there and you will find people who recommend each of them. Most people only have experience on one or two. Comparison charts don't exist as far as I know, and even if they did they wouldn't be unbiased. The other thing to remember is that most longarms can be purchased with different options, and some of those options are important to some people and not to others, so configuring a longarm is a very individual experience. Here is a link to an excellent article about purchasing a longarm. (You have to go to the bottom of the page, put it in your shopping cart, but it is free.)
http://www.quiltsonthecorner.com/inc/sdetail/1349