Since this is my very first serious project, I have a goal to learn as much as possible. Spent some time measuring the components. They all come really close to each other. What I was able to discover though is that the LSK170 jfets are not B grade, but F! I was able to find just a single explanation for the F grade which means "free samples". I've measured their IDSS and discovered that they are on the lower end ~4-6mA. I am suspecting that the difference between +/- and the lower value comes from the fact the the jfets between bc550/bc560 measured ~5.7 and ~4.5mA. I have some with higher IDSS(but one is just bellow 6mA). Been digging the thread and saw you wrote that more close, higher idss ones should be placed on the leftmost position, bellow/above bc550/bc560. What about the rest? Also, should I just order a new b grade batch with higher idss from a more reliable source?It basically works alright given your test numbers. If you want to try bring the rails closer replace with bit stronger VF led in the chain of five. IRFP9240 side.