I've just bought a brass/ruby one. It looks really great for the gift I have in mind - and delivery early May will leave me some time to play a little with it before giving it ;)
BrainFlushYep. I have a very cheap and convenient 3x mirror bought at the local "Carrefour Market". It has high plastic edges and no top has ever gone over them. It is large enough (13.5 cm) to accommodate my worst spins. It also gives me better spinning times than any other surface I tried: Eisco glass, Lawson base, ForNeverSpin "diamond-like" base, other mirrors (I didn't try K9 glass though).
I also have a cheap 30x-60x microscope (https://www.amazon.fr/dp/B01D5PB3Z2/ref=pe_386181_51767671_TE_dp_1) and I check the bearing balls from time to time. It takes some time to use it properly; it requires to find proper incident light and proper distance from the top. At 60x magnification, I could see a ~0.1 mm scratch, which is a few micrometers in real size. On some of my rare stainless steel bearings, I can see the machining circles. If I pass a wet finger on a ball, I can see its traces on it (same size as the said machining circles); I'm sure what I see is the trace of my finger because it changes direction when I change the direction of my finger on the ball. Until now, I've seen no scratches on any of my tops with bearing balls, even on my two ruby ones. What I see at the tip of a ForNeverSpin top is the Grand Canyon.
BTW, I enjoy using this microscope to admire the polish of my tops. Some of them are amazingly good and I like such good work as much as long spin times.