No need to worry, I often feel like what I'm doing is a waste of time. I do agree with what someone else said though as I feel like whilst the sequential reads and writes on most boards are largely the same, the random reads/writes are a little more varied and this may be what people are looking for. In either case, if a £5 card performs largely the same as a £15 card, I'd say it was worth doing for the money savings. Whether that £5 card will last as long as the £15 one is a different matter but hopefully with some of the other tests I'm doing, we'll find out!