We've no issues yet. The nice thing about this ash additive is that is adds zero hardness, so while the pH is now 7 (where by the way it has been since 2001) there is still zero GH and KH. My tanks run at pH 6.0 (115g) and 5 (70g and 90g). My chocolate gourami are spawning non-stop, I have half a dozen fry in the floating leaves, also other fry I can't identify yet but suspect they may be pygmy croaking gourami, pencilfish are spawning...so they are quite happy.
It is the proposed lime that worries me, but early indications are that it will be minimal hardness. That means the tank will lower in pH naturally, and pwc will not affect it due to the biological equilibrium. This has been my case for 15 years. But we are at least aware of whatever may come.