Can I run my own catching software instead of the Transcom engine?

Yes. The VPS is sold as a purpose-built, well-positioned catching node, and you are free to run your own dropcatch software on it rather than the Transcom engine.

You still get the two things that make it valuable — the ~3ms proximity to the Nominet backend from Iron Mountain Slough, and the multi-core specification for running many parallel EPP sockets. What you put on top is up to you.

This makes the box a good fit for registrars catching under their own Nominet TAG who already have a catching stack and simply need low-latency EPP access from a proven location.