Well I would take the better speaker every time.
yes you can connect most subs to both a two channel preamp and receiver at the same time. It is important to have the inputs sum. If they don’t it will not work so read your manual or give them a call. I do this with my JLs and it works well.
I would also encourage a higher crossover. Your subs are better than the speakers below 80hz for sure. Try 60, I bet you get more impact and lose nothing.