After wasting $$ on a backup bulb that didn't last (but was out of warranty from sitting on the shelf), I've come to the following conclusion:
1) If you already have an extra bulb or get one "free" (like you did): great, save it
2) If you want to BUY an extra as a backup: don't, because either you're old one will last (and if it makes it anywhere near 3000 hours, that's a LONG time) or the new one will be bad (and you don't know it unless you use it--and you won't know after 10 or 20 hours either); replacement bulb prices don't really go up in price anyway.
Yamaha RX-A2050 AVR (5.0.2)
(4) Polk Monitor 10B's (R/L F/R), (2) Polk Monitor 4's (TM), Polk CS300 center channel
Analog: B&O TX2 Turntable, Nakamichi Cassette Deck 1
Digital: Pioneer CLD-99 Elite LD, Panasonic DMP-UB900 UHD Blu-Ray
LG 65EF9500 4K OLED