Music Hall Cruise Control vs Pro-next Speed Box for MMF-7

Any experience with either ( or both) units appreciated. 
Looks like the speed box does not have adjustments for speed control.  Just 33/45.  Is your tt running off speed?  You need a KAB strobe to check it.  If it's not, I would leave it alone.  If it is, I would probably buy the Music Hall, as it has speed adjustments in stepped increments. But you will need the strobe either way.