Would you register a name starting with a number... like 10bestplaces.com? Any SEO concerns? It's amazing how hard it is to register a keyword-rich-domain... I am sick of all those parked, never used domains...
numbers in domains do not matter for SEO. they matter a lot for other reasons. good luck having people remember your domain, for example.
For example 10 top baby names 100 top baby names was a very good domain to grab. look in key word suggest and find the ones people are looking for.