Faster in this case does not mean noticably or measurably faster. Maybe a few microseconds for a simple comparison like that. Joins show more of an effect, but you still need to be doing huge joins to notice.
Use the appropriate data type for the data value that you are going to store. Test. If performance is unacceptable, then come back and do strange things (like binary(8) in the name of performance)
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)SQL In The Wild
: Discussions on DB performance with occasional diversions into recoverability
We walk in the dark places no others will enter
We stand on the bridge and no one may pass