You can taste the effect of sun dried cakes with XZH, who've made that one of their calling cards over the years. Just recalling on memory, their are pics of sun drying cakes (in the sunshine) for their '11s. So that year for sure, but I think it goes back aways (on Houde, the emphasis is on sundried maocha and not cakes).
As far as effects go, I'm not sure I could say very much. The most notable aspect of XZH processing is how often the tea is relatively fermented (usually in the acceptable range). The aroma is usually a pretty stable performer over the years, and aside from Yiwu Chawang from '06 and '07(flaky performers), they seem to be aging well, with increasing depth. There are so many things that can affect performance that I'm not sure it makes a huge difference.
Going with Nada's tea (I just had his '10 Mansai today, incidentally)...I think other things are at issue. The '10 Mansai really did suffer from handling, more than anything the difference between bing drying methods. In general, maocha handling/fixing in the field swamps *everything* first. It's a matter of greater skill at that, such that this matter of bing drying matters. That's a good thing, at least. I suppose the effect is from open air drying only equalizing the humidity within and without the bing--none of that damage that comes from storage in very dry places. The speed of drying may also matter.
I could imagine the '10 Nadacha being fuller (and I suspect Nada's words in my vocabulary means louder taste as well), but I'm not sure the Manmai and Bangwei would have had much difference, due to the character of the leaves. The Banpen, given my minimal experience, I suspect would have been a very large difference, even in the short term. And in '11, the tea from Nadacha is getting fuller at the expense of a bit of complexity in my care. The chief difference in 2012 that I've noticed is the superior thickness and texture. I may not have been happy with the fresh tea, overall (aside from the really expensive Bangwei), but I've grown to enjoy thickness, in part from these '12 teas, and they contributed much to my tea awareness and capacity to enjoy tea.
I would much like to hear from the puer.sk peeps about this, as well. I think Scott does too many teas to really handle the extra attention sun-drying of bings would require. The performance of Scott's tea from '09 and '10 can't contribute much to the discussion. The '09 tea I have were Bulangs made by a third party, and we have no details on their manufacture besides some Xiaguan-ish production defects that they are recovering from. The '09 fall DingJiaZhai has aged rather poorly, given my one try, in that 'hey, it's high and hollow', but in a more problematic way than the '10 Nadacha has been to date. Compared to a '08 DingJiaZhai sourced by finepuer.com, this is dead obvious. Storage differences also play a role, but I don't think that explains the qualitative margin in aging nature. The '10 Yongde Xue Shan has done better. Started out thin and higher tasting with some complexity, and by the time I finished the bing, it filled out some. However, I cannot seperate out all the different factors, because I've not had many Yongde teas besides a DaXueShan that's of quite different character. In the end, sun drying might have helped that one, but overall process still swamps, like having bulges of nasty dust filling part of the bing. The '10 fall Xikong has always been notable for being a rather meaty and full tea for Mengla small-leaf. Drinking the tea this year has mostly seen defects (when they occur) of the not-enough complexity kind, and not lack of fullness and depth. Outstanding tea makes outstanding tea, and sundrying is a matter of polishing a cut diamond...