What are some alternatives?
When comparing A1 Sitemap Generator and RiveSolutions SEO Spider, you can also consider the following products
DYNO Mapper - Create Sitemaps with the DYNO Mapper Visual Sitemap Generator.
Screaming Frog SEO Spider - The Screaming Frog SEO Spider is a small desktop program (PC or Mac) which crawls websites’ links...
WonderWebWare Sitemap Generator - Sitemap Generator is freeware program that will help you to automatically generate site maps for google, bing and yahoo in their respective file formats.
Checkbot - Checkbot will boost the SEO, speed and security of your site by checking you're following 50+ web best practices. Browser extension with free and paid plans.
GlooMaps - Create your visual sitemap on the go - easy peasy
Beam Us Up - SEO crawler software lets you discover broken links, uncover missing page titles, duplicate content and identify other problems.