Hi Svaros,
I just used D-47 in a large batch of sweet show mead. I live in So Cal and the temperature has been hot (although the last week has been warm but not hot)
Anyhow, the D-47 has been a remarkable yeast to this point. The temperature has been a constant 75 degrees F and the mead has not suffered in the area of taste, or fermentation. I am very happy with the results thus far. The D-47 took off very quickly (it was bubbling away in less than 12 hours) and went very strong for two weeks. I let it slow down for a week and racked. At racking time there was a significant yeast cake on the bottom.
The gravity was around 1.038 or so if I remember correctly off the top of my head, and the mead smelled very good. I pulled off about a half liter from each vessel before racking and I must say that for a three week old mead, it is already very deep. It should mature to a very, very good end product.
I plan on making other batches using Lalvin yeasts as I am very impressed with the character of the D-47 and am curious about the K1-V1116, 71B-1122, and the EC-1118.
I noticed that you were going to get some of the commericial meads to get a baseline idea of where you stood. That can be a mixed bag. I've tried a few of them and the styles, ingredients and actual characters of each are all over the map, so if you're not sure what you're looking for it may be a good idea to pick some up. On the other hand, because they are so all over the map character and flavorwise it can be difficult to focus on what you like and move in that direction.
You can "flavor-average" like a lot of wine makers/drinkers I know do. That is, you find the flavors and characters you like in each mead, and then find out what the building blocks of those flavors are in the brewing (mazing for the purists out there), fermenting, flavoring and aging process. Incorporate those aspects that you like into your brewing process and then focus like a laser beam on perfecting your technique.
Hope that helps,
Oskaar