It's slightly shy of 1 full year with the skate sharpener.
Last May we bought the machine after careful consideration reading reviews and making contact with Sparx directly for more detailed information. We knew of one other family who had the machine and they had nothing but good things to say about their experience.
Our boys used the 7/16" radius wheel, they sharpened their skates a total of 102 times over the course of their season. That's 102 sharpenings combined. We were skeptical at first as I read several different reviews, many of which were in support of, while there seemed to be quite a few against as well. Those of whom were against seemed to be more of the traditionalist who will only have their skates sharpened with a stone. Additionally, a good chunk of those against were also skate shop owners who are completely against personal skate sharpening machines because it takes revenue away from them. I get that and completely understand their point.
With that said the machine has paid for itself over the course of the season and then some. Yes one grinding wheel lasted the entire season. All of the grinding wheels are something like $57 a piece but if you take into consideration the cost of getting skates sharpened in a shop versus doing it yourself after it's paid off, you will be saving a lot of money.
The machine is small and sits on a bench in the basement. Both boys have no problem sharpening their skates on their own, 13 and 15 yrs old respectively. Knock on wood, we haven't had a single problem with the machine, including cleaning, and switching out grinding wheels.
If you've been thinking about buying your own sharpening machine, I absolutely recommend Sparx. It's simple to use and their support staff is great, they answered every question I had about grinding wheels on two separate occasions, same day.