If you are goiong the QFX5000 Series route vs EX4600, even though EX4600 and QFX5100 are the exact same hardware, difference is SW, I would suggest going with QFX5110 vs QFX5100 - has all plus more. If any product is nearing a point of becoming End of Sale, it would be QFX5100 as QFX5110 has been a better option for a long time, EXCEPT for QFX5100-48T. In 2020 when QFX5120-48T becomes an 10GBase-T option, then End of Sale of QFX5100 may occur sometime after.