You don’t have to choose between having it or not, you can have both. Just ask your audi to create a new/duplicate program from your default P1 General program into P2, then add Speech Rescue to P2. That way you can do A/B comparison by switching between the 2 programs to see how different they are. If you don’t like it, then remain in P1 like normal. If you like it, or when you’ve become accustomed to it and want to use it all the times, then next time ask your audi to add it to P1 permanently and get rid of P2. Or just leave as it and whenever you feel like using Speech Rescue, then go to P2.
I’ve used Speech Rescue extensively in ALL my programs with no issue at all. If it sounds like too much lisping for you, then just adjust down on the Strength setting until it sounds more natural. I’m not a professional musician, but I do play piano and drums, and when I play the piano, even on a pure tone note, I don’t notice anything funny to me (like something is off tune). But everybody’s musical ear is different, so I can’t say that you won’t find it off-putting. But at least you can try it in P2 and decide for yourself.
Actually, I really enjoy it when listening to music because I can hear a lot of high frequency timbres and tones lost to me before now restored. The Oticon frequency lowering is based on frequency transposition and composition, instead of frequency compression as used by other hearing aid brands. So I personally think that it lends itself much more natural to music and not cause off-tune sounding weirdness because it’s not like the whole high frequency range is compressed.
If you want a completely pure music listening experience, you can always ask your audi to add the MyMusic program into one of your 4 programs, and not have Speech Rescue enabled in there, but use Speech Rescue for normal everyday non-musical listening environments. Or you can have 2 MyMusic programs with 1 not using Speech Rescue and the other one using Speech Rescue and decide for yourself which one sounds better. Then just delete one and keep the one you wanted after you know which one you like better. There are a lot of ways to experiment.