Center recommendations to go with CMT-340s L/R

I recently replaced my 170s L/R speakers with 340s. I'm using one of the 170s as a center, but want to replace that. Looking at center recommendations, it seems likely I should get a 340 center, but wanted to see if moving to a Sierra 1 center would make a noticeable difference.

Pretty sure I already know the answer for this, but want to make sure before pulling the trigger...

Thanks for any input
ButchW

Go with the 340 center, it will be seamless.

The Sierra-1 is a better speaker all around, but it has a bit more of a relaxed sound compared to the 340.

I think those cbm 170 vertically should work pretty well with the cm340.