I have one.

Its fun.

But on the subject of rolling codes, I was able to get through a security gate that relies on, essentially, a garage door opener.

The exploit relied on the ridiculously low amount of rolling codes it cycled through.

Capture one, and try it a few times to get through.

Cars are more robust. Despite tinkering with it for about 8 hours, I wasn’t successful with defeating it. That being said, I picked up the device, in part, to start messing around with various signals as an educational tool.