The UH400x range have a soft turn-off as well as being fast so they produce a lot less switching noise as a result of the 'snap' turn-off of the reverse currnet that flows for a short time when the diode gets reverse biased. On normal 50/60Hz ac supplies that effect is not normally a problem. (When you get up to SMPSU switching frequencies it is a very different matter!)
I have seen simple linear PSUs where there was an issue with EMC (mains conducted noise) which replacement of the 1N540x range devices with UF equivalents solved. It does no harm to use fast, soft-switching diodes at mains frequencies, and might help to keep EMC problems to a minimum.
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