FACT: all electronics fail over time
- Servos: Typically the gears wear out and need to be replaced eventually, factor in the cost to replace these gears plus the cost of the servo, if this adds up to more than buying a new servo, then pass on the deal
- ESC's: Hard chassis slaps from off-road use tend to shock the internals which break loose on the circuit board and will eventually fail, doesn't matter which brand you get all ESC's are "ticking time bombs" which can't be predicted how long before they fail... of all the brands I have personally owned, HobbyWing tends to last the longest and when they have failed on me, HobbyWingDirect.com offers deep discounts on replacement
- Motors: Only buy a motor that offers replacement rotors/sators/sensor boards, these are common replacement items that wear out... I've seen a guy damage his sensor board on the very first pack after a bad crash! Many budget brands do not offer replacement parts, consider these brands disposable.
- Batteries: Age quickly, heat is the worst enemy for batteries, use IR readings to tell you the health of the cells, where <3mΩ is considered low IR, and <7mΩ is what I would consider acceptable for resale, I would not buy any pack without current IR readings. I always post pics of the most recent IR reading with any pack that I sell... if the IR is >7mΩ then I simply keep the pack as a "practice" pack or simply give away my older practice packs and I discard any pack with IR >15mΩ
- Chargers/Power Supplies: These electronics tend to last the longest, and tend to hold their value the best
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