Have they bought for my bike because I check the valve clearance and adjusting itself. The feeler gauge is sufficient for absolute, it is true of the size intervals not the finest -> always in 0.05mm increments, so 0,05-0,10-0,15 ... etc. but with some sense you can also adjust the valves so that one intermediate areas as 0.17 hits (0.15mm fits well - 0.20 does not fit). In general, it is indeed rather a bit too much valve lash than too little because not harmful (but enough already!). I have therefore the valves already set appropriately, following maintenance is no obstacle! Can recommend so the lessons!
