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The 2022 Grom has a 5 speed. I wish my Z125 had another gear.
As for a Navi, I personally don't see the appeal for myself when things like the Grom/Z125 exist. They're just way too much fun and worth the added cost IMO, at least at current pricing after fees. I'd also rather have an actual scooter with storage under the seat and a flat floor board to make it more practical. Then again, I picked up my Z125 for $1700 with 40 miles on the odo and I've never ridden a Navi so maybe my expectations are out of whack.
Now, I do think the Navi is great for someone like my GF who is legally licensed but doesn't like riding the Z125 I got her due to the clutch and thinks scooters are too dorky and in some cases too large for her short stature.