What are some alternatives?
When comparing SEO Crawler and XML-Sitemaps.com, you can also consider the following products
Screaming Frog SEO Spider - The Screaming Frog SEO Spider is a small desktop program (PC or Mac) which crawls websites’ links...
DYNO Mapper - Create Sitemaps with the DYNO Mapper Visual Sitemap Generator.
Pulno - SEO Audit and Website Analysis. Pull up your SEO.
GlooMaps - Create your visual sitemap on the go - easy peasy
Netpeak Spider - A desktop tool for fast and comprehensive technical audit of the entire website.
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.