I was so happy to get my single convex yunzi stones from Yellow Mountain Imports today. I placed my order on the 20th so it only took eight days for them to arrive.
The first thing I noticed is that the white bowl is significantly taller than the black bowl, but they seemed to be about equally full. Upon examination it became clear that the black stones are not only smaller in diameter than the white stones, which was expected, but also noticably thinner as well, which I didn't expect, but was certainly fine, and makes sense given the fact that if they were the same thickness they would be out of proportion.
My bowl for the black stones was a bit lopsided, which I found to be quite charming actually. The lids fit amazingly well. I actually had to work a little the first time to open the bowls. I can imagine transporting these bowls strapped into my Ishi travel bag without worrying about the lids coming off.
I have not washed nor treated the stones with oil yet, and I am not sure if I am going to bother to do so. I like the feel of the stones as they are. I really like the thickness, and since I bought the smaller stones they fit well on my Japanese sized board. They are a little more difficult to remove from the board than double convex stones. I find it easier to remove them with a thumb and index finger rather than with the index finger and middle finger that I use to place them initially.
Where these stones really shine is in game review when it comes time to play out a variation. I decided to try them out with a game from Go World. I chose the first game in issue 95 (Summer of 2002). The game was titled "Meinen Magic in the Fujitsu Cup". Even though I have the Go World Digital Archive I happen to have a hard copy of that issue. I found the game in Smart Go and made a copy of it to load in my Go World tab in Smart Go and renamed the record GW095-01. Pak Yeong-hyeon was white and O Meien was black. I read through the commentary for each figure before I added the stones to the board so I would know to stop for commented moves and to play out variations. I clicked through the record on my tablet pc and had my hiba board next to it. As I clicked through the game I placed the yunzi stones on the board. When I came to a variation I put out the stones upside down. It was so easy to remove the variations after I was done playing them. All I had to do was look for the flat stones and pull them off the board, and I didn't have to worry about messing up the main line of play.
These stones are a pleasure to use and a value when you consider that you are getting stones and bowls for one reasonable price. I would recommend them as a first set of stones to anyone.
I'm actually thinking that I might like them better than my slate and shell stones that I paid over $500.00 for. Maybe I will sell them some day so I can buy more go books.
I am considering using these to mirror my online games to slow myself down and to force myself to read looking at real stones instead of the computer screen.
I love my single convex yunzis.