Well, like I said I don't live in the SEO world as much any more. I do my own SEO for my sites but don't keep up with or use any canned software. Not really sure you need it.
The things to be careful of with any SEO software are 1) Leaving a footprint that SE can easily identify. Once a bunch of people start using the same program it can be easy for the SE to spot a site optimized with the sw. This has happened with a couple well known programs. 2) Doing rank checking with SEO software. Some engines don't like all the bot traffic and it's easy for them to see you are working hard to optimize your sites if you are constantly checking your rankings. 3) Submitting. You really don't need to submit any more and some engines like G like it much better when they spider the page as opposed to being force fed the link. So I don't submit any more at all. I just hit my pages with the G toolbar and link them to my MSN blog and a couple other places and they get picked up faster and ranked higher IMHO. In fact even my newest site
www.5starblogs.com got a high ranking and PR 5 right out of the gate and I never submitted to a single SE. Never even got sandboxed. Already Alexa 140,796 too. Barely even promoted it.
I just use the FREE Digital Point KW tool for KW research and love it.
http://www.digitalpoint.com/tools/suggestion/
Bunch of other tools are listed here:
Cool Tools 4 Affiliates - SEO & KW Tools Too
and
Top FREE SEO Tools - 150 Award Winning Tools
Hope this helps and best of luck!