For what its worth i had a cheap one off the bay a few years back, no more than £60 posted roughly, filled my super 10 bottles and s400 for about 2 years without any issues. Im back with a hills pump now which cost £45 posted off here, does the same job just more well built. The trouble is with the cheap ones if you read some reviews it seems they’re not all built the same, one could last years and the other a few weeks, also alot of them are the same pump with a diffrent name, at least with the hills you know what your getting when you part with your cash.
Atb
Chris