This is certainly the simplest approach I've seen so far, and I'll definitely keep it in mind for future use. However, I'm currently using something closer to graff's approach. I need to have a count of the invalid items encountered in the input stream, so I've defined a CHECK function to be used by :encoding(utf8) that ticks up a counter of the number of bad things found and then returns the unicode WTF?! character to replace it in the input stream.

As for the relative speed of getline (<>) and read block, I was recently working with a system where benchmarking showed the speed difference between the two approaches was quite substantial -- 7-8 times difference -- which is why I wanted to avoid getline in this case, especially since my processing needs are not specifically line-oriented.