Cassettes and cassette decks, I don't care how high end, how expensive. All of them to degrees have limitations. As they're about convenience, and less about long term durability and reliability under heavy duty use, and holding those specifications with age. Speed is not the only compromise here, track width is another compromise. Wider the tape track is, the higher the speed is, the better the frequency response is, the better the signal to noise ratio is. Open reel machines have a 4-8 times advantage on track width, and have usually a double to 4 times speed advantage over a cassette machine. I can print higher operating levels on an open reel machine like my Otari MX 5050 B II with today's super tapes than a cassette will ever be able to. And no CRO2 or Metal tape, or NO NR systems necessary. A cassette deck built my way would weigh 40 pounds, but there'd be no belts, and 3-4 huge AC motors driving it, a 1" thick deck plate, plug in cards for the electronics, all alignments up front, and built in tone oscillators. And there'd be NR outboard, and the 3 3/4 IPS speed as an option, and optional single direction 2 track Stereo for even better performance.