I never owned Pennies before, I've always been a Juliet fan. But I actually ended up loving the fit of the Penny!
Penny on the left (ruby) does not have a serial number, Penny on the right (greenJade) is a serialised PB01xxx pair. I also learned that the serialised pair has got a bit of a darker colour (the way I see it) compared to the other Penny and my 4th gen Juliets. The serialised Penny also does have some tiny holes, casting marks. Comparing the two, it looks like the newer Pennies are brighter and shinier and smoother. I love them both!
Penny on the left (ruby) does not have a serial number, Penny on the right (greenJade) is a serialised PB01xxx pair. I also learned that the serialised pair has got a bit of a darker colour (the way I see it) compared to the other Penny and my 4th gen Juliets. The serialised Penny also does have some tiny holes, casting marks. Comparing the two, it looks like the newer Pennies are brighter and shinier and smoother. I love them both!