I have an AU-7900 that I recapped last spring (along with new trimmers, new thermal compound, replacement of fuse resistors and a few other updates), but I did not do the "sandwiched" tone and filter boards at that time I'm getting around to them now, and given the relative difficulty of getting to them, I was thinking that perhaps I should just go ahead and replace the 2SC1313 and 2SA726 transistors at the same time. Any downsides to doing this? The unit sounds quite good, with no noticeable noise or distortion. My goal with the recap and other work was/is preventative maintenance, as I intend to keep this unit over the long run and then pass it on to one of my kids. Thank you!