The BMW 5 Series E39 is widely considered by purists and experts as one of the best sedans ever produced by the Bavarian brand, if not the pinnacle of the 5 Series. Launched in 1995 (and in 1997 for the Touring wagon version), it introduced aluminum suspension components to reduce unsprung weight, offering an exceptional compromise between ride comfort and dynamism. The facelift (LCI - Life Cycle Impulse) in late 2000 brought the famous luminous ring headlights (Angel Eyes), revised bumpers, and the new generation of M54 engines. Although its build quality is remarkable, its advanced age now requires rigorous maintenance, particularly for the cooling system and suspension components.
The BMW 5 Series E39 is a future collector (and already is for well-maintained versions). Its purchase today should not be taken lightly: a cheap E39 to buy will cost you a fortune in repairs. Prioritize 6-cylinder petrol models (525i, 528i, 530i) which offer the best compromise of reliability/maintenance cost/pleasure. M57 diesels (530d) are excellent long-distance cruisers provided their intake manifold flaps have been 'deleted'. Avoid V8s without a clear timing chain history. Plan for a refurbishment budget (cooling, suspension components) to enjoy what remains one of the best sedans in the world.