the only problem i have with jetts is they don't have actual weights written on the machines, not sure if its the same at all jetts, but at mine they're all labled 1, 2, 3, 4 etc up to 15 or more so i have no idea what i'm lifting, especially since all the weights are different sizes.
my assumptions are ab crunch machine is 5kg increments, chest press & fly, lat pull down, static rowing and leg raise machines are 10kg, leg press and olympic bench 20kg increments, but i'm most likely wrong. can't find any info on the manufacturer's site or the jetts site and there are no staff around when i am to ask.
the free weights have weights written on them but thats all.
otherwise i recommend joining, they're certainly good value, for me mainly that you're still able to use all the gyms across the country for the base rate, where as if i wanted that with fitness first for example, i'd be paying something like $37 a week - that and jetts is a 5min drive from me and they're open 24hrs so i get home, have dinner, watch some tv and then hit the gym at 10pm.