Do you think the 40's and the SE center will timbre
Match?? The SE's use the same drivers a tweeters as
Studios. (So they say)
Sure, the SE's do use Studio drivers, the cabinets are more like Monitors.
Since the SE's will be put to less demanding surround duty I don't think you would have a problem at all and you'll probably LOVE the 40's for your fronts.