Started my OTTI brewing with the Den's Kunpu. This is the light steamed shincha offering from Den's. I'm still pretty new to tea, so take this for what it's worth ...
4 g. leaf, 5 oz. (150 ml) water, unglazed kyusu
Dry leaf is attractive medium forest green color, a noticeable quantity of long green needles but more small pieces -- i.e., it won't look as needle-y as the picture on the Den's site.
1st steep, 160F, 60 sec. Light green color, clear liquor, some particles made it through the obi-ami screen. Flavor is rich green vegetables (think asparagus or artichoke), a very slight bitterness, and little to no grassy flavor. I was pretty happy with the result, just enough bitterness to give it some additional character, but if you like a more "in your face" tea, it can probably stand up to a longer steep without becoming too bitter.
2nd, 165F, 15 sec. Very similar color, more sediment coming through. After the particles settle it is quite clear. The light color for a second infusion had me thinking I had underbrewed, but I don't think so. Flavor was similar to first infusion, the rich green veggies are still there, but the tea has a brighter flavor -- I'm guessing this character is what I've seen referred to as "high notes". Everything is quite a bit bigger, better balanced, and a bit more complex, although still coming across to me as a pretty mellow tea.
3rd, 180F, 30 sec. Continuing in the direction of the second, the focus is moving away from the richness and more towards the bright flavors, with additional bitterness. This tea doesn't seem to be changing as much as I've seen with some other senchas. I think it peaked with the second infusion.
4th, boiling 60 sec. Still making a drinkable cup of tea, so maybe I did underbrew some of those early infusions. It has faded quite a bit, and I've had a lot of tea by now, so I'm just getting the impression of "green tea". But not bad at all, and I wouldn't hesitate to do 4 infusions with this tea. In fact, I may do another.
Overall, I thought this was a good tea. Maybe a bit simple and mellow, but very pleasant and easy drinking. I'll be interested to hear the opinions of those who favor a more intense, "full-throttle" sencha.