Use whatever you like best. I use a road helmet for recreational road and mountain biking. I use a Giro with visor for commuting, since my commute in the morning is east bound and evening is west bound (so I head into the bright sun on my commutes).

I know the higher end Giro visors are removable. Check to see if the one you are looking at has a removable visor (then you have a dual style helmet).