Not grand seiko spring drive, grand seiko quartz. Caliber 9f.Perhaps, but their specification [spring drive] is +/- 15 secs per month. IME, that's the same real-world performance I see from any quartz, even cheap Casio/Timex models.
It's possible they outperform this specification. Certainly, most mechanical movements outperform their specifications when carefully adjusted. For example the Miyota 9015 spec is -10 / +30 / day. I have 2 watches with this movement and with careful adjustment their real-world performance is +3 / -1 per day.
"QUARTZ | MOVEMENT | ABOUT | Grand Seiko" https://www.grand-seiko.com/us-en/about/movement/quartz
Pretty cool that Seiko takes such pride in a non disposable quartz movement. Monitors temperature 540 times a day. Has an adjustment dial on the movement if it runs fast or slow.
The spring drive, automatic and high beat calibers are quite accurate but not worlds better than eta or whatever. The smooth movement of the spring drive is pretty cool though, but it's worth remembering that back before quartz watches, people spent extra on watches with a 1s/beat automatic movement. Not something you see much today.