Louis Rossman is, if nothing else an entertaining character. It seems to me he's quite an expert, maybe a wizard repairing Macs among other things. (There's a video of him somewhere retreving data from a USB pen. Actually repairing the pen's logic board.) Its really amazing to see him identify problems and solder tiny tiny connections on logic boards.
His criticisms of Apple seem reasonable to me, if not totally spot on, he surely has a lot of experience with Mac problems, why they happen, and sometimes why Apple could have done a much better job.