I've an SXT G-2HnD that I upgraded out of curiosity:
uptime: 3d6h43m21s
version: 7.1 (testing)
build-time: Dec/01/2021 14:07:27
free-memory: 5.5MiB
total-memory: 32.0MiB
cpu: MIPS 24Kc V7.4
cpu-count: 1
cpu-frequency: 400MHz
cpu-load: 17%
free-hdd-space: 109.9MiB
total-hdd-space: 128.0MiB
write-sect-since-reboot: 10705
write-sect-total: 2895979
bad-blocks: 0%
architecture-name: mipsbe
board-name: SXT G-2HnD
platform: MikroTik
It's quite responsive. Free RAM is about 3MiB less than it was when it was running 6.49.2
Only 7 basic firewall rules though and single core as well so I doubt it's capable of doing anything more advanced with the resources available!