MEDIUMBLOBs vs. LONGBLOBs

[David Johnson]

Hi!
My project has a bunch of tables with MEDIUMBLOB columns.  There is a very,
very tiny possibility that we will eventually exceed the MEDIUMBLOB size in
the distant future, so my bosses are suggesting we just go with LONGBLOBS
everywhere.  Is there any extra performance cost to this besides the extra
bite for the size?

Thanks!
DJ