I wanted to use "review" but I believed opinion will be better when comparing BANS vs phpBay(Wp plugin) vs phpBay API vs free option. If you don't know, all 4 will let you list eBay items on your site. Like BANS, you pay only once to get phpBay.
I will take each one and give my opinion on it.
BANS
Positive: Simple to use, more secure than phpBay(WP plugin), themes, less cpu resource hog than WP+phpBay(WP plugin)
Negative: Require you to use a MySQL database and will use more space than phpBay API and WP+phpBay(WP plugin)
Opinion: If you are just starting(no real html/php experience) and don't want a blog, BANS is the one for you. Of course, using AuctionSiteWriter will help in the setup of your BANS faster. ;) If you have a blog, you could add folder to hold the BANS. You would need 2 MySQL databases in that case.
phpBay(WP plugin)
Positive: It's a Wordpress plugin so it's simple to add. I did used the free version(too basic) but I got the paid version because it does offer me more options for my blogs. No need for a new MySQL database. You can cloak the links and and even filter out words. That's a nice option and using it. The reader can select the country and see items available to them.
Negative: It's more Wordpress fault here thus it's less secure since it's using Wordpress. Just read my post about it here. Now, imagine 100s of blogs like that. It also take more resource(space/CPU time) than phpBay API but less than BANS sites.
Opinion: If you already have a blog or a few blogs, why not list items at the end of your post that might interest your readers. Personally, I would not start a big network of WP+phpBay(WP plugin) blogs just to list items on it. I already added phpBay(WP plugin) on my other blog.
phpBay API
Positive: The base code take less space(20KB) vs 6590KB(BANS) vs 4200KB(WP), no MySQL database required. More flexible.
Negative: You need to know some coding before using it. No themes.
Opinion: The potential is there but it does demand more from users. After looking at it, I started to support it in AuctionSiteWriter. I'm sure I will find a way to make it much simpler for users. The fact that you don't need a MySQL database is a big factor to me. It's one less step and some hosting package are limited on the number of MySQL per package but not with Host Gator. I bought a few pre-owned domains and used AuctionSiteWriter to generate a 1 page parking page instead in just 1 minute.
MyStarterBlog + MSB eBay Plugin($7 each)
Positive: The base code take less space(100-150KB) vs 6590KB(BANS) vs 4200KB(WP), no MySQL database required. Not a CPU hog on the server, more flexible, secure(no backend), use themes, RSS feed, sitemap.xml, no footprint.
Negative: You need Windows.
Opinion: I'm biased here but it's the least costing solution of the paid ones. Also, since you "Generate" the site on your computer, you have an automatic backup.
Free solutions
Positive: Free
Negative: Limited
Opinion: I should point that eBay has a free snippet available but don't offer the cloaking aspect for example. I also did not use it. Also, phpBay(WP plugin) has a free version. It's was too simple for me but it did give me an ideal.
Conclusion
Some will tell you that you don't need BANS or phpBay at all since free options are available. It's true but it also depend on your overall need too. Setting up a few WP blogs is not the same as creating a network of 100s of "stores".
Each site has a solution that's a better fit for it. It also depend on your own skills. Adding content on a regular basis on a blog, thus updating WP more often, is not the same has a "set and forget" site. Maybe it's me but I don't want to hunt down for plugins, deal with trackbacks or security issues thus BANS or phpBay API is a good solution for the "set and forget" sites.
But since I'm using this blog as my flagship general blog, don't be surprise if I add posts using phpBay(WP plugin) soon. I already modified a few popular post using the free version but will add other kind of post to see how it would perform by attracting new search engine traffic. Of course, I will upgrade that plugin to the paid version. I already have a series in mind and will be original content.
That's the beauty of having my "name" in the domain name. I'm not bound to anything. :D
Edit: To show Frank C(comments) some examples, I used phpBay(WP plugin) paid version. Noticed that I could sell the item to US, CA, UK ... thus possibly increasing my sales. That's something that I like. I did not change the default colors. The second example adds categories(617), keyword filtering.
[phpbay]Die Hard blu-ray, 6[/phpbay*]
[phpbay]Die Hard blu-ray, 6[/phpbay]
This is the same thing but with categories(617), keyword filtering . I just want the Die Hard movie or Collection.
[phpbay]Die Hard blu-ray, 6, 617,"harder vengeance live 3 4"[/phpbay*]
[phpbay]Die Hard blu-ray, 6, 617,"harder vengeance live 3 4"[/phpbay]
Ebay script
Edit 2009/04/20: I added MyStarterBlog
Keywords: 1and1, affiliate, AuctionSiteWriter, BANS, BANS, Business, eBay, Freeware, Host Gator, Hosting, Internet, Money, MySQL, opinion, phpbay, resource, Review, Shareware, Software