Conclusion after the first 300 km: POSITIVE: I bought the battery for this season (bought last year9 ) because I read that the Trotti should have a bit more power, about 20%. The speed was never very important to me, 20Km/h is usually enough, but I live on a hill and noticed that it reduced to 16-17Km/h up the road to me. Straight ahead it always runs around 21/22 Km/h. With the additional battery, I get up the hill at 19/20 km/h and can now master gradients that it couldn't manage before, or only with a lot of walking home or pedal assistance. It has a lot of power and is now a real joy to ride. The range is actually a good 40 km. The thing can handle gravel, grass, asphalt and parquet (research) effortlessly, even in the rain it cuts an elegant figure. As elegant as a scooter can be. I kind of hung up my sex appeal and my masculinity with this thing anyway. All in all, it's a cool piece. And protal cool with underbody lighting. NEGATIVE: - Although the workmanship looks solid and apparently high-quality plastics and metals were used, the thing rattles like a pig when it's being hauled. I can't decide whether I feel more like Werner, whose bike brakes spread out when going downhill, or Cool Runnings on the final lap. Probably a question of time until the thing flies apart. - Suspension travel = 0 . Even with Smarties, it bangs under the carpet and sounds awful. Category "that sounds expensive" to "but now something has broken". - Appearance mentioned above - Until the battery is fully charged, you've got worms. It takes 12 hours for the thing to really go from dead to top condition. - Firmware flash for ES4L (ES2L with battery) useless, tuning not possible (unless I'm too stupid. That CAN be, of course).