MIMF

The are various lookalike systems on the market over quite a price range. The Jet models apparently being close to identical and the priciest. Then there are the much cheaper knock-offs which get reviews from "ok for the money" to "better off betting the money on horses".

Anyone got some personal experience?

I use waterstones for most work and now when something needs a lot of metal remove I use pretty coarse sandpaper on a piece of stone kitchen work surface I rescued from a dumpster.

Quality of the stone matters a LOT. My experience is that the inferior stones are either too soft and wear out or get clogged up and constantly have to be dressed.

Sold my T-2000 recently after an extended period of running it side-by-side with a low speed 8" grinder with CBN wheels. Much faster than the Tormek for routine flat grinding, and the aluminum wheel tends to suck up grinding heat, so the edge stays much cooler. Turners have been using the technology for years, but I resisted due to the square face wheels (which favor jigged use). TFWW finally brought out a crowned face 80 grit 8" wheel. and that allowed me to freehand grind on a Veritas grinding support.

Tormek is moving into diamond wheel for their sharpeners, with the low speed a good fit for abrasive that breaks down at the higher temps seen with dry grinding at higher RPMs. You might check out when the new wheels and (I expect) a new model might be out soon that leverages wet diamond grinding. There are also CBN wheel for the Tormek available in the aftermarket for dry grinding, but unless you really need the jigs, a $100 low speed Rikon, $150 8" wheel, and a $50 grinding support gets a reliable system for about half of what I see new Tormeks running...even without the stone truing stuff needed with any friable wheel.

CBN stands for Cubic Boron Nitride, a type of ceramic, which is nearly as hard as diamond but doesn't have the issue diamond has of being absorbed into iron and steel at higher temperatures. A good rule of thumb is to only use diamond wheels on carbide, never on steel. That said CBN isn't universally recommended for carbon steels which may cause glazing so to be safe I'd only use CBN on tool steels. Low speed wet grinding should eliminate all the problems with both diamond and CBD wheels.