This was recommended to me a few years ago by my piano tuner. I have a grand piano that I inherited from my Great Aunt. I love this piano, but the cats are very hard on it (it seems to be a trend). They don't scratch the piano on purpose, they just seem to be very clumsy and they've marked it up pretty good (or bad as the case may be).
When the tuner recommended this product, I ordered it right away. It's so easy to use (you just wipe it on and wipe it back off), but the results are astonishing! Here are a few before and afters to give you an idea:
Lots of scratches and an unattractive cloudiness.
I swear this next picture is the same spot! (It's still a little wet, hence the blotchiness.)
Next up, some fairly deep scratches, but they're no match for my Restor-A-Finish!
Ahhh, so much better!
It doesn't last forever, so it needs to be redone fairly regularly, but given that refinishing this thing is nowhere in the cards, this is a wonderful alternative!
The Restor-A-Finish comes in other colors too! (I use Mahogany on the piano and Cherry on some other, lighter furniture.) And, just for clarification, I'm not being paid to talk about this product. I just love it so.