Just one more info : the RXQual measured in SFH is artificially lower than in BBH. It doesn’t mean the voice quality is worst in SFH than in BBH.
You must perform Voice Quality measurements in order to know that for sure.
It’s interesting to test BBH vs SFH, however:
1/ SFH is so easy to use, considering the high amount of freq you have… Just properly downtilt your antennas
2/ it requires VQ measurements, to get the full picture.
Regarding radio coverage (indoor penetration, for example),
Radio coverage at the cell edge is enhanced when Hopping over 4 or more frequencies. This is known as “frequency diversity”. That increases radio quality (a lot) & radio coverage (a little), compared to No Hopping.
If you have 4 or more TRX, then it means the TCH will hop over 4 or more frequencies, which is optimal for Frequency Diversity, regardless it’s BBH or SFH.