This kit is a basic cleaning kit all guitarist/bassist should have. You can do routinary cleaning after playing with the "one" liquid or polishing the finish with the polishing cream. The fretboard oil is amazing, no residues or sticky feeling after applying it and only a few drops are good to oil a fretboard.
While it is a bit more expensive than other brands, you don't need to use that much to get a nice result.
Note that this is only for guitar/basses with a gloss finishes. For mate finishes I can recommend the MusicNomad Guitar Detailer MN100.