Hub motor vs mid-drive for your first conversion: the honest trade-offs

Rear hub (geared, 500 W class): cheapest ($250 to $400 kit), simplest install, no extra wear on your chain, quiet. Weak on long steep hills if you are heavy, and you lose quick-release.

Front hub: easiest install of all, two-wheel drive feel, but torque on a thin aluminum fork is risky. Torque arms required, steel fork preferred.

Mid-drive (Bafang BBS02/BBSHD, Tongsheng TSDZ2): uses the bike's gears, so it climbs anything and keeps the wheels stock. Costs more ($500 to $900), wears chains and cassettes faster, needs a standard 68 to 73 mm threaded bottom bracket, and you must shift like you mean it (ease off while shifting or you eat drivetrain parts).

Flat commute: rear hub. Hills or trails: mid-drive. Budget and curiosity: rear hub, you can always sell it.