Advice for Straumann Bone Level Implants in posterior mandible?

I am planning placement of four Straumann bone level implants in LL5 LL6 LR6 and LR7 site. I would be very grateful if you share your thoughts on the size of the implants I have selected. I also wonder if tapered effect Straumann implants would have any advantages in that case. I am considering of splinting the crowns especially on the left side. Thank you in advance.