Since my last post I have been to Poland via south of France, N. Italy , Austria and Czech republic to see the "Flytrap" plus a few trips to various rallies. On the downside I had a big end fail due to a faulty crankpin. other than that it has been fine. The big end bearing and crankpin was replaced with a UK made bigger better set, and at the same time all the bearings were replaced with European ones.
I have managed to set the ignition timing correct ( It was too advanced and combined with a badly heat treated crank pin was jointly responsible for the bearing failure) It now runs smoother and with more "pulling" power. It is happy from the low forties (MPH) up to the low sixties. still turns back about 95MPG (Imperial). It has now done 16 k miles and still on the original Indian made primary chain. Although those are lifed at 18K miles. I have a genuine Reynolds to replace it this winter. It eats Indian made rear chains at about 6k miles, but the cheaper Italian Elite chains are twice as good. At 3k miles significantly less worn than a new Indian made one.
I find I make on average more miles per day on the Enfield than I did on my faster BMW. Partly because I only need to stop once a day for fuel and partly because it is much more comfortable and less tiring. Just seem to bumble along quicker. Bit odd I know.
You will need to carry more tools because they seem to have decided never to use the same size fastener twice. If you have to undo three nuts/bolts you will need at least four different size of spanner.
The only thing that was better on the BMW was no chain maintenance. The problem is that the Enfield is oiltight and you will need to oil the chain daily if doing significant mileage. There is not room enough to use X or O ring chains.
Apart from the chain, I just do an annual maintenance which is good for 3K miles. more than that requires an oil change (DINO cheap oil).

I use soft luggage except for a givi top box. and have an Avon (Sprint) full handlebar fairing like the 1960's UK police. This keeps rain, insects and road debris of my upper body and there is no windchill to my upper body. If I could find one I would have used something similar to the old Avonaire touring fairing for all over protection.

Hope that helps.