4 instead of 'four' in short domains

[33S]

hi. do you guys think using '4' in short domians (like 6 characters) is more preferable than 'for', because it seems although '4' is not very serious, but it gives advantage of having a short domain name, which i think overweighs having the '4'. what do you think?

p.s. as one person on another forum said, "a domain has to be short like a gunshot"