It increses headroom so basically more clear sounding and less noise maybe from what I understand. Everyone pretty much agrees 18v is all that's really needed and 24v is negligible from what I've read but people do the 24v mod because it's really small compared to even only two 9v batterys let alone three. THe only potential downside I can see is that the batterys are slightly harder to find in storesand though may not cost more they have way lower millamp ahour on them so they'll wear out faster. I still need to try the lithium 9vs to see how they react and last but my battery hasn't wore out yet and I still have a packe of alkalines too. - I'm betting a normal lithium 9v woul dbe great compared to alkaline because they should stay are peak voltaage longer. I transfer my 9v's to other stuff after they hit about 8.5 volts. That's the point I can tell stuff isn't feeling or responding right after when I test them after taking them out.Does it just give more clarity?