That's great to hear, thanks.
After watching the video I mentioned, I went out and rigged up an aux load in parallel to run my immersion/geyser, and as you say, it works perfectly.
It's comforting to hear that you've stress tested it like that, and that you've had it running for so long now. Thanks for the reply. 👍
I've been trying to get an answer on this for ages and see somebody actually do it before I commit to it myself.
Just found this video pop up on YouTube. He's done it successfully by the looks of it.
https://youtu.be/A14GhJvw8Dk
Might help someone else......