Porta Pro is really small.. retro look thats been retained since 1984, i dont like their metal feel and smell, have doubts if they dont rust... catches on my hair bit too many times as well when i borrowed it.
They do seem to have an preference for the vocals, but also really good for Drums haha aka Rock... nice impact really impressed with it.
Thankfully they don't sound like Grado 'phones, which I dislike. Bottom line is that I sold my Grados and still have and listen to the Porta Pros. At home only cos they're open - iems rule on the road (although I've yet to buy a set that I'm truly happy with for SQ).
What the OP is probably misinterpreting is that Grado and KSC35/75/portapro's both have the general bright sound with sparkly highs. They don't share the same drivers, as they each develop their own drivers. But I do find that my Grados do mids a bit better and KSC75's have slightly better bass.
While my new portable setup (lossless + Nuforce Ne-7m) bests my home setup (lossless + portapro) I will say that after using the 'pro for years, I love the sound.
They sound better than the modded ksc-75 the my ears.
I really don't get it when people call these phones bassy. I find them balanced, non-fatiguing, but with little overall clarity.
Nice for the price though.