i would not say submitting to botw is waste your money, but your best option is split the budget to other quality web directories.
The submissions form allows you to suggest the category... they just reserve the option of placing it elsewhere if a more appropriate category is available. Nonetheless in ANY directory your chances of getting one you're shooting for are enhanced if you submit there instead of leaving it blank. If you leave it blank the reviewer HAS to select one entirely on their own... whereas if you submit to a specific cat the reviewer has to go to an extra step if they believe it is a mismatch. I've been on the review end in directories for a decade. In most directories there will be more than one place that a site would fit. In my experience, human nature is on your side if you give the guy on the recieving end a nudge by submitting where you want it (assuming it IS one of the ones where it reasonably fits).
I think its still worth it for SEO purposes, especially if there is isn't a whole lot of other websites in the same category.
I managed to get a sponsored listing on a PR 6 page and it did seem to help me on the SERPs though it could have been coincidence. I wrote them when I submitted my site and asked them for a specific category, which they gave me. I don't think I would pay for a listing without PR though.
I had a sponsored listing from BOTW but on a PR N/A page. Didn't seem to get any benefit from it or see any loss when I cancelled the subscription a year later.
stop worrying about pagerank....no one cares about pagerank anymore. BOTW is a good trusted directory and IMO a listing in there is worth it.
unfortunately a lot of people (including submitters and webmasters) do still care about PR and until google totally devalues it they will continue to care about it if you are looking to build links for your site you should be looking for a related category/page on a good quality site with uniquely written content the PR on that page is not always a good indicator of how useful a link there will be imo