Originally posted by bonovox First, there are now two versions for this 3rd party battery grip. Some improvements
were made to the 2nd version. The maker has even a supporting post on a
Chinese photo forum, which is good.
无忌论坛 - 【产品专题】[Travor旅行家] 讨论区-手柄,电池,充电器!-新品S350PRO专业级手柄上市!
This bay listing is not clear about the version.
I bought from the same seller, I believe what I have is the old version. The battery
slider door is not firm, the two wheels are not that smooth, comparing to the
wheels on the Pentax body. Other than that I was happy, so far.
Someone on that Chinese forum did mention that after some use, the wheels
became easy to operate.
Also, the maker said that both door and wheel problems have been fixed. If you
could read Chinese: "最近不会升级.但是现在拨轮和电池仓的缝隙都改好了." or maybe
use Google translator?
I would suggest double check with the seller to find out the version, if you do
want one, you want to get the newer version.
Hope this helps.
Pinwu