I bought an ebike 2 years ago and it's a game changer, especially as my partner takes the family car to the office 3 days a week. It's much, much cheaper than a car but gives me the same freedom for shorter journeys (up to 30 mins in a car), which is most of them.
The motor helps me with the hills so i don't get sweaty and allows me to have a heavier, more comfortable bike with suspension, pannier bags for carrying things and a cycle seat for my child. Means I can do pre school drop offs/ pickups easily and actually, it's quicker than taking the car in traffic, and reduces the cars on the road. Obviously its not great in rain but its not too bad. Ice is my biggest no go but happy to use it any other time of the year.
I got it from a local cycle shop so it's legal and I ride it same as a normal bike, ie not on the pavement, careful of pedestrians etc. It does annoy me when other cyclists take the piss as you feel it makes it less safe for you. So I'm all for charging them as you would car drivers going through red lights.
There are some a-hole drivers who hate cyclists and aggressively overtake on narrow roads but I take great pleasure when I go past them as they hit traffic or a red light, which always happens around here! Sometimes it feels like everyone is out to get you but I'm reality it's a very small portion of drivers, maybe 1% or less. Probably similar number with bad cyclists.
Basically, there are a-hole drivers and cyclists so we should not ban everything but just do things like this to control dangerous behaviour. You have to remember though, a car can easily kill cyclists or pedestrians. Cyclists on a legal ebike are unlikely to kill anyone. The speeds are much slower. You don't even need traffic lights at those speeds as its slow enough for humans to react at junctions like in Amsterdam.
I wish escooters were legal as would love to have that option too for short journeys. You will only see a-hole escooter riders and dodgy cheap flammable batteries because it is illegal! As with anything, legalising and setting safe rules for their use would work better overall. You will still get a-hole riders but why punish the many for the actions of the few. Just imagine how many cars we could take off the road if both were more common and safer.
I think the Kryptonite and Abus brands are supposed to be good but not sure if they'll have anything for that price.
You could try finding anything with a 'sold secure gold' rating. It's not the highest level they have but will hopefully carve out the brands that bother to get a rating.
Another good bet is to pop into a local cycle store with decent reviews on google maps