Superstar are generally known for cheap and cheerful componentry, but this ISIS bottom bracket is both cheap and impressively long lasting.
Most original ISIS units use skinny cartridge bearings squeezed between the larger splined axle and the shell, which meant super short lifespans.
The Superstar uses larger diameter bearings running on surfaces machined into the axles and shell, plus massive lip seals on the outside.
As a result we haven’t had a single squeak or other issue with these despite months of singlespeed abuse and they're still spinning silky smooth.
There are loads of great ISIS cranks in bargain bins too, so getting a complete bargain crank system should be easy.