The concern is not just transformers, but needing repairs, finding replacement parts, etc. I know from previous experience living abroad that "standard sizes" vary from one country to the next, and particularly between Europe and the U.S. That being said, I have run my lathe and grinder off transformers in the past (we lived in Eastern Europe previously and I assumed I wouldn't be able to find quality machines at a decent price so I brought mine with me and invested in some transformers) and it worked out.
As a turner, I only have a couple of machines: lathe, bench grinder, band saw, but I have done larger builds as well and was hoping to take advantage of my time in the UK to pick up some new quality handtools: planes, chisels, saws, etc. (I always appreciate a good excuse to pick up a new tool)
We will be living near Regent's Park, so I recognize an excursion outside London is likely necessary, and indeed - welcome! We will have a car, so driving somewhere outside the city, or even a few hours away, is definitely a possibility.