Thanks, that is very helpful. Like Ken I have an Axiom Pro 9 which is about 3 years old so should be capable of running LH4. Even with LH3 I have noticed that sometimes it can be a bit slow.
The radar is a Quantum 2 so there should be no issues there and instruments are an i70 and the original ST 5000+ autohelm. The transducers are ST 60’s which connect to the i70 via an ITC-5 and the autohelm connects via a SeaTalk-1 to SeaTalk-ng converter kit. The transducers can be calibrated easily through the i70 so that should not be an issue. I cannot control the autohelm with the Axiom and I am sure I would want to anyhow but it does transfer basic data such as DTW, BTW and XTE.
I have found Raymarine Support very helpful in the past so I will email them to ask if there are any issue with my set up and LH4