The answer depends on how much work you want to do. Do you already have All-In-One SEO on your site? If the answer is yes, did you fill in the SEO description and title fields under the post editor?
Why Stay with All-In-One-SEO
If you have had All in One on your site for some time and have used it for the settings page and that’s about it. Then I would recommend, I would highly recommend you not switch to WordPress SEO unless you are willing to do a lot (and I mean a lot) of work. Otherwise you will be committing SEO suicide.
WordPress SEO For New Sites
If I were starting a site from scratch I would probably use WordPress SEO. But it isn’t easy. You can’t just use it when you want and skip it when you don’t. WordPress SEO demands that you use it or you will pay the price. You had better read and understand the settings as well, otherwise you are in for an SEO nightmare.
You have to fill in the options on each post or page. Don’t and your SEO is worse than if you didn’t have an SEO plugin.
Issues with WordPress SEO
Twenty Ten Double Double Title tags
I recently setup WordPress SEO on one of my small sites using a Twenty Ten child theme. The first thing I had to do was change the title structure in the header.php. If I didn’t it would repeat the title tag. You don’t want double title tags. Once is all you should need.
Permalinks set after Draft Save
As noted in the previous post. If you have WordPress SEO activated you have to manually update the permalink if you change the title. This has always been the case once a post is published but with WPSEO you have to do it after the post is saved even in draft mode.
Meta Data, FILL IT IN OR ELSE
You have to fill in the Meta Data portion of the plugin on each post, if you don’t you don’t have a description. If you don’t have a description the search engines grab whatever is available for a description and it isn’t pretty or helpful.
This is not the case with All-In-One. You can fill in the excerpt (which has always) been the description if filled in in WP or the first paragraph is picked if not. But with WPSEO if you don’t fill in the Meta Description you don’t have a description.
Static Home Page or Blog
It makes a difference with WPSEO. If you have a static home page the SEO title and Description are set from the page you have chosen for the home page. If it is the blog you set the home page title and description in the SEO Titles section. But if somewhere along the way you decide to change to either a static page or blog page home page, it will screw up your SEO Description and title unless you remember to go in and change the settings. If you don’t you won’t have a description on your home page.
There’s more, a lot more, but I’m not going into any more details. Just consider the consequences when using WPSEO.
All-In-One SEO is much less invasive. Use what you want, or let WP do it’s thing. It is up to you. Not so with WPSEO.
There are some nice features to WPSEO. But don’t think you are going to activate this thing, fill in a couple of settings and forget about it.
I just changed all my existing sites back to All-In-One. I’ll leave the decision up to clients when setting up new sites. If they want to be sure to fill in everything, every time. Or do they want to set it up and let it go.
I have almost a 1000 posts on some and over 400 on most. If I want to use WPSEO I have to go back to each of those and fill in the Meta Description for each otherwise, I end up with meaningless descriptions showing up in search engines. I’m not going back and fill in several thousand descriptions.
My recommendation for most, stick with All-In-One SEO if you already are using it on your site, you won’t get in near as much SEO trouble with it as you can with WordPress SEO. If you aren’t willing to take the time to setup WPSEO and then fill it in EVERY TIME, I’d pick All-In-One SEO for your SEO Plugin.