It really depends on the number and locations of sites. I think fiber and microwave at every site would be awesome, but geography and budget constraints hamper that.
The reality is, we connect sites with the best means available. When need be, a site is linked via microwave to a point where we have fiber in place. I am not the biggest fan of linking with DS1 unless it is a cell site, but that is just me. I like knowing my stuff links my sites, and is maintained to my standards and fixed by my people. Cutting out middlemen makes me happy.