Hi brother, and welcome to the brotherhood.
Yes, I have experience with it, and sorry if this offends you, but I tossed that and a few others into the recycling bin. The auto pumps that are compact at that size could not function properly, and has tons of issues. I'll list them:
- Pressure accuracy. You don't pump according to the safety margin of pressure based on where you are in the PE journey, you will injure yourself. At the same time, the pump that small lacks the proper pumping pressure to provide you what you need. Most auto pumps pressure sensors can wildly swing between +/-15% to as big as +/-50%. That's quite dangerous when it comes to your penis safety.
- Improper safety measures. During a pump, if you feel something is off, there's no control in depressurizing the vacuum pressure immediately. Within 5 seconds, you can destroy your penis. This is not a joke, and it's very real. Many people suffered due to the lost of pressure control.
- Lack of pressure control. In your PE journey, you have to maintain a proper pressure range over time. The starting point is around 5inHg to induce growth. You need to slowly increase 1inHg over time and cannot jump too fast forward. This is how pumpers destroy their penises. You also need control over the pump to increase and decrease through dynamic pressures. Dynamic pressures helps to trick the penis that you're still in a safety margin, but at the same, you want to cause a temporary micro expansion trauma to induce expansion growth.
Auto pumpers cannot do that. Bathmate does not allow you to know the pressure beside the "feel". Most cheap version pumpers out there is a Russian Roulette system even with a gauge. Something to think about. Since you're in the brotherhood, ask questions and do not feel like your questions are sili. Ask like your penis's life depends on it.