This is just my opinion, but there are probably studies that agree, the URL doesn't look "attractive" with numerals in it. Then again, several years ago they said "never use a hyphen in your URL" and now they're not uncommon.
Of course there are well-established URLs, e.g. 9to5linux.com, that can get away with it but given a site that I didn't already know about with numerals in it, I wouldn't click the link, personally. But like I said, that's just me. Perhaps your site would be in the Top 20 most visited in the world for all I know.
Seems like a lot of work that could be better spent creating awesome content.
Of course there are well-established URLs, e.g. 9to5linux.com, that can get away with it but given a site that I didn't already know about with numerals in it, I wouldn't click the link, personally. But like I said, that's just me. Perhaps your site would be in the Top 20 most visited in the world for all I know.
Seems like a lot of work that could be better spent creating awesome content.