My fiancé has a tuxedo with tails (it comes with a top hat and cane which will be used for pictures and things - not the ceremony itself) but the Best Man and Groomsmen do NOT have a tuxedo with tails. They have the typical black 2 button notch tuxedo with a long tie (not bow tie)....
Do you think that will look weird? Should they be in tuxedos with tails too?