I know nothing about imaging so i am not qualified to give any input but i would say visually a noticeable improvement with the TMB lense cell and every scope whether imaging or visual would benefit from a feathertouch ,here is the scope you are looking for with a 4'' FTF but would shop around for a better price ,nice looking scope
https://www.optcorp.com/william-opti...h-focuser.html
Hope that helps