I built the Bafang mid-drive BBSHD with a 48V/14A battery. It has ~4000 miles on it now more or less. Battery is doing well. I don't ride full throttle much. It isn't built for speed, It is built for hills of which we have many so its top speed is maybe 25 mph.
The bike has had it's issues. Worn out wheels, tires, brakes, seats, derailleurs. I learned how to buy better than bottom of the barrel components but never the best components.
The Bafang kit needed a steel gear replaced inside and I did that myself. The nylon gear that is inside was the natural failure point I thought but it hasn't failed. I am careful not to lay on the throttle when there is slack in the drivetrain (chain, sprocket). Pedal away from a stop on pedal assist, then add throttle as necessary
Base bike: 2008 Trek 4300 that I already owned b/c our budget was thin back then
Tire upgrade: from stock Bontrager tires which wore quickly on pavement to Schwalbe Marathon. Still have these tires with thousands of miles on them.
Brake upgrade from Trek rim brakes to Tektro budget cable disc brakes (~$20 per wheel). Rim brakes wore through the rims at one point.
Seat / handlebars: Origin 8 parts
Wheels: Wheelmaster wheels. Did go with Bontrager for the second set but the spokes stretched and needed adjustment often. Wheelmaster wheels are more utility like, larger diameter spokes I think, affordable.
Charger: Luna Cycle 80/90/100% charger. Early on the chargers would fail regularly. The last one is a few years old now. I always charge to 80% or less. I park it with ~30-60% charge if I can. If I'm not riding it, I store it with ~50% or so in the battery. Sometimes I charge in the evening. Sometimes I wake up early and charge in the early morning. Always outside or with the open garage door or on the porch so I can toss a flaming battery into the yard. Smoke alarm. Never a battery problem.
Lights:
https://www.brighteyesproducts.com/ and Ascher USB Rechargeable LED Bike Tail Light 2 Pack I'm on the second battery pack of the light. Taillights are 3-4 years old.
Locks: InBike Folding Bike Lock Orange Anti-hydraulic (Amazon, off-brand) and 12mm Bicycle Wheel Portable Locks (locking cable loop), bright color locks so the thief might be deterred
Advice: depending on where you work and live don't leave it outside with any lock unless you can absorb the cost of replacing the bike. A cordless grinder will cut through any lock quickly. Lock advertisements will show how hard they are to cut with a manual lock cutter. The manual lock cutter isn't the real threat in my opinion.
At home, mine is in the garage. At work I park it inside the bldg near the room where I work. I don't charge overnight, usually just in the evening before bed or I wake up at 5AM to switch on the charger for 3 hours. I have plenty of hours to do that. I store the battery in a surplus 40mm steel grenade ammo can (I think that is the size, I can check if you like).
We also have another ebike commonly seen delivering food in big cities. It has been a good bike. ~1500 miles. Was ~$1200 several years ago. Uses very common ebike parts so even if the manufacturer can't supply parts, I can find replacements all over the web.
Hope this was helpful.
