I spent about £250 on my Quest 2, and feel I got good value on it. As well as being able to watch VR porn, it has a decent selection of VR games and aps that are often reasonably priced. I don't regert buying it. These days I use it a lot more than say my Xbox.
The Quest 2 is also standalone, meaning that you don't have to connect it to a PC or other device to pay.
You can off course get cheaper headsets, but that will result in drop in quality. I feel that the Quest 2 is a good balance between cost and quality.