do you know where they did there measurements at? Top, bottom or middle of the cylinders?
I sonic test all my blocks in all three locations, top, middle and bottom on all four sides
If the measurement for #1 cylinder on the cam side is at the middle or top I might be a little bit concerned, if it is at the bottom I wouldn't worry at all
I do have to move the sonic tester around at the top of the cylinders on the cam side due to that head bolt boss being there also, you can find some blocks that will have a tiny area that is really thin, say the size of a half dollar, a two inch diameter circle, and be really good around the rest of that small area