Ethan Dicks wrote: If the solder joint in question meets the following criteria: a) bad enough that fail-open is a credible risk b) in a pathway such that fail-open could cause damage to other components (particularly hard-to-replace ones) I'd say it should be retouched. In any other case, I'd say that the risk of damage, plus the loss of historical value, are convincing arguments to leave it alone. Bottom line, though, is that they are your kits, and whatever you want to do with them is Ok. Good question, though. - Mark