I like very scrappy log cabins with narrow logs, so for me, the strip method, and then squaring up, is the best way. I like having the freedom to make design choices every step of the sewing process.
If I were doing a planned, limited fabric choice lop cabin quilt, then I could see some value to cutting pieces before sewing.
My preference in log cabins is for that traditional, scrappy, vibrant effect. I just think it makes for a more interesting design. I think having some variation in the widths of the logs works well too. You can still have the blocks end up the same size, by trimming your final block.
RST