Any advice regarding carrying one of these devices?
I tend to lean towards having one, better to have one and never need it than to need it and not have one.
Any advice on which type, experience with them etc always appreciated

This one is worth a look: https://gtc.co.uk/products/motorola-defy-satellite-link

I've been thinking about getting one

In reach - offers two way communication so you can send and receive messages and get tracked but requires an annual subscription[ also have " free" set messages you can send

PLB no annual subscription but its a pull once and get rescued - more piece of mind as you cannon send messages or be tracked - certainly the s cheapest option and the pure safety net - think they largely only work UK as its more for marine purposes but not certain

Defy - no idea its new not got and never tried but it does not do tracking.