I have both of these....The Leopold is better..
Someone who has both keyboards 
Do switches feel close to each other? I think they should because both are linear and have approximately the same actuation force. How much louder is Leopold?
And thanks for your insight.
The Plum isn't linear...It has a very light tactility (which is why it isn't a great Topre replacement) but the light tactility is probably because the force need to press down is less than 45g Topre. It feels like 30g/Topre.
The Silent MX on the Leo feels somewhat Topre like in that it is solid, stable and has a similar sound...and has a similar feel when you're pressing down but without the tactility at the top...
I'm happy with both to be honest...The Plum works out for work because I don't care if I lose it..it is still close enough to Topre to keep me happy...
The Leopold is fun to type on as well but you have to be ok with typing on Linear switches...I like this keyboard for gaming the most though..really really good...