A good match: yes, probably so. Spendors are typically fairly efficient and easy to drive, both attributes that CJ's tube gear likes.
Resale value: A'gon says $1080 and $510 for MV-55 and PV10AL, US dollars. Actual resale price here have been 10% to 20% lower, though there appear to have been some successful sales of PV10s at higher prices.
Tubes can last 2000-5000 hours. Tubes in preamps can last longer than those in a power amp. As an order-of-magnitude estimate, suppose you listend for 1000 hours a year. By the end of the second or third year you'll notice that the components seem duller, less dynamic and colorful; then it'll be time to get a new set.
The sets CJ sells are decent and will be fine, but might be a bit overpriced relative to what you get elsewhere for the same amount. A full tube replacement set (8 tubes) for the MV-55, for example, is roughly $180 (USD) from CJ.
Resale value: A'gon says $1080 and $510 for MV-55 and PV10AL, US dollars. Actual resale price here have been 10% to 20% lower, though there appear to have been some successful sales of PV10s at higher prices.
Tubes can last 2000-5000 hours. Tubes in preamps can last longer than those in a power amp. As an order-of-magnitude estimate, suppose you listend for 1000 hours a year. By the end of the second or third year you'll notice that the components seem duller, less dynamic and colorful; then it'll be time to get a new set.
The sets CJ sells are decent and will be fine, but might be a bit overpriced relative to what you get elsewhere for the same amount. A full tube replacement set (8 tubes) for the MV-55, for example, is roughly $180 (USD) from CJ.