Dan,
It would be interesting to see how you attached your wires to the LGB masts/hoops or the wooden poles on your mk1 system.
They certainly both looked sturdy and robust.
I bought a load of the Mk1 LGB system in the late 80s and early 90s. This has the non-adjustable bases and the stainless steel fixed length wires with U loops as joiners. I bought loads of this just as Beatties were getting rid of it at stupid prices.
The original stainless steel catenary wire is very strong, but by matching the sectional rails available, the lengths can be restrictive on your geometry and some special masts, with cut back bases were always required for points etc. I either used flat metal plates under the track to support these cut masts, or stakes driven into the ground.
I bought loads of spare arms too, and when I needed a few more masts, I was able to get the Mk2 versions and swap the arms over. I have never bought any of the modern masts with adjustable bases.
It has been very well used on temporary layouts ever since, but for the past three years most and now all of it, has been in my garden. Apart from me breaking a mast by being clumsy (easily fixed with Super glue) it has fared well and proved cat and fox proof.
I have never seen any of this stuff second-hand in shops, but looking on e-bay I see it can be picked up from e-bay Germany and also US for less than £7 per mast, which is roughly half what the modern ones cost. (I have previously bought loads of other other items from Holland and Germany and found it cost effective, without any nasty customs charges!). I can heartily recommend it.
If I was starting out with LGB now, I also could not afford to put up wires if I had to buy everything new at full price, but I could just about scrape together enough to afford these!
James