Twenty years ago or such, replacing a felt would mean to purchase some felt remnant and then cut to size. Honestly I never managed to do a good job with that, excepting perhaps the occasional external horn machine or Victrola where the excess could be trimmed at the outer edge by using the turntable itself as a template. In any case I don't have good memories of this work: once I almost cut a pair of my fingers by trying to use a worn 12'' record as template. Most of all, I hate to see poorly trimmed or mis-centered felts wobbling left and right when the turntable is spinning.

I've seen that recently some pre-cut replacements have become available. This sir in US seems to offer pre-cut felts of any custom size, in a nice assortment of colours (quite oddly, he doesn't mention the word "gramophone" in the title of his ad):
https://www.ebay.com/itm/Custom-Cut-Rep ... PFiU7W07pA
Did any of you ever tried these replacements? Are they really well round and well centered?
Any similar product available in Europe, perhaps?