Sunchai, I think it's pretty obvious that you are either part of the Smart Flex L-Plate design/engineering team and/or an interested party in marketing and selling the Smart Flex L-Plate.
This is not a bad thing! But please be open in disclosing your background and relationship to the Smart Flex L-Plate. The GetDPI community is a bit different in that we enjoy having dealers/manufacturers participate. It makes us feel important. Seriously, though disclose your background and relationship. You're getting very real feedback from experienced medium format digital photographers---and everyone here wants to see innovative companies adding to the medium format digital experience succeed.
Thank you Sunchai, and welcome to the GetDPI family.