Oh, the 7450's look pretty damn bad... they're rated 47dBA. I'm fan noise sensitive so 47dBA is an extremely high number to me. (Really, anything over 38dBA @ 1m is irritant level.) For comparison, the 6610's rated 39-48dBA @ 1m. So the 7450 actually is as loud as the 6610. But the 7450 doesn't state a low-side number, so I honestly don't know how quiet it is at low load. Any time it's going to be under high load, I'm already going to have hearing protection on anyways.Also keep in mind, the FCX and 6610/6650 platforms are NOT the same CPU/architecture as the 6430/6450 and 7xxx series lines. The 6430, 6450, and at minimum the 7450 and lower 7k switches are all ARM-based CPUs, not whatever the others use (PowerPC? I can't remember) so they suck a LOT less power just by default.
I agree that you're probably SOL on lower-power with BGP through the ICX line, but just on the off-chance you haven't, have you actually checked out the noise on a 7450? I've had them running on my desk for pre-deployment configuring and they're not really that loud, even the PoE ones. The FCXs and the 6610s are screamers (ESPECIALLY the PoE ones), but I haven't found the 7450s that terrible.
Of course, I haven't had one permanently parked 10 feet from my chair either, so yeah.
Really there's no reason to not have BGP other than market segmentation on Brocade/Ruckus' part. Contrary to popular belief, unless you're doing some really big tables, BGP is noisy but not high CPU demand. Usually it's RAM. For a smaller environment (couple dozen /22-/32's,) even something like the Juniper EX2200-12CT can handle it with ease. You sure as hell don't want it trying a significant table, but you could very easily do a pretty robust anycast setup on even an ICX6430 without putting a dent in performance. And with the 7000-series on a common ARM architecture, it kinda surprises me nobody just copy-pasted the bgpd over to a lower switch.