I do a KB class once per week on a Monday at 6am. Its an awesome way to start the week. I do pretty much everything (swings/squats/presses/turkish-get-ups) with a 16kg although some of the routines we do include doubling up and doing squats and presses. (2x16kg)
Overall as others have said, i’ve just seen an improvement in overall mobility and core strength. Highly recomend you get someone to show you what to do. I found that with a 12kg, my technique was poor, however moving to a 16kg improved things massively. If you’re based Manchester way i can receomend a very good coach/trainer
Dave