Hi Pramote,I have the 30mm,24mm,70 and 120,I have the 180 on order.. all CS(except the 24mm which is not available in CS)they are all extremely good in every way.I find the 120 to be excellent for landscape,it is very sharp at infinity but it's a slow focusing lens,I am looking forward to getting the 180 as it is 35mm EFOV of 140mm and focuses much faster.
I haven't used the adaptor but I spoke to people that have and the HC!00mm and 35-90mm are very good,focus is fast and everything works as normal,(metering ,exif etc)
You can also use the hc300 which is a fantastic lens...
If you would like a sample file of the 24 or 120 just let me know and I will send you a DNG..
best
Rob