PS: I see the Microshift 7-speeders feature shift cables that come out of the sides of the shifter bodies, like your old RSX units. When Shimano decided to put the shift cables under the bar wrap, likely for purely aesthetic reasons, this introduced a lot more sharp bends, associated friction and shift problems that was only solved with super-premium lubricated cables, and higher derailleur spring tensions. Plus the new shifters eat cables regularly. About 1/4 of the shifter problems we see feature 'eaten' cable ends, now irrecoverably jammed somewhere in the shifter body. The older Shimano shifters, with the exposed shift cables rarely did this.

So this is another aspect where the Microshift shifters are superior: less cable friction and superior 2-paddle ergonomics.