Benefits far outweigh the potential drawbacks (nothing in the world is perfect & flawless). You'll get rid of the periodic 'tuning' and the morning starting issues. Just keep the cooling system nice and proper (use only long life coolant). Dont get overzealous with engine washing (esp. when engine is hot, dont wash at all!) - keep the oil maintenance and filter-changing (oil, air, fuel etc) on time - and you should have a trouble-free vehicle.
Naye gari kafi arsa theek chalti hai - bas chalana ana chaiay.