They both say they're the brightest they do! Don't know if the 'exposed' looking ones are more prone to moisture damage?
 
Well my drivers side gets a bit of condensation sometimes. Just thinking when theyre on, they would spread light in all directions filling most of the headlight, where as the other one would give a more 'projected' light? Thnink i may prefer the latter effect?
 
You're absolutely correct... that is a stupid question! :p Just kidding. They do come in pairs, i understand what you mean tho as some people only need to replace one at a time etc.
 
Haha thanks, I couldn't tell as it didn't mention they come in pairs and it has the quantity box at the bottom

£9 seems a good price for two, ideal