Dave,

If you're concerned about looks vs. strength, and you're using 8' pieces of BS1088, I would put one scarf joint in between the two 8' pieces and one in between the 16' mark and the last foot or two. But as Kyle said, it really doesn't matter as long as you do a good job with an 8/1 scarf. The only advantage to what I said is that there's only 1 wide one. After doing finger joints (a la Duckworks.com) I'm going back to scarfs as my friend Don has proven to me that a well planed scarf can almost be invisible.

Regards,
Brad