My wife and I camp at Burning Man for a week every year, and we camp irregularly in Death Valley over Thanksgiving. Our gear gets seriously abused at Burning Man with temperatures, sun, and alkaline playa powder. Rubber especially takes a hit from the combination of sun and powder.

It's been my experience that some expensive things don't last any longer than cheap crap, especially where rubber is involved: O-rings and hoses. I've given up on expensive camp stoves because replacement parts are hard to get, are expensive, and shipping costs as much or more as the part. I can get cheap Chinese stoves as cheaply as, say, Coleman stoves with having to replace rubber parts every few years. When the cheap stove fails, I just toss it and get my backup stove out. I hate to have to throw the whole thing away, but not as much as I hate paying more for replacement parts than for a whole new stove. (As far as I can find, cheap stoves are sold as is and have no replacement parts available anywhere.)

Camelback-style backpacks for water fail at the O-rings after one year, maybe two. It's easy enough to replace those from the hardware store plus carrying a replacement. I haven't found that cheap copies are less durable than expensive ones (well, my wife bought a child's water backpack because it had a look she liked - it failed quickly, but you expect that).*

Tents are another issue. We buy expensive tents, and they last for years. We've bought the artificial fabric tents with flys and wash them in the tub after we get home, then dry them out. Lube the zippers with dry lubes of various kinds. Eventually, though, the fabric gets frail from sun, powder, and stress from high winds, and it parts at various seams, generally at stake points. Cheap tents tend to fail in the winds. My preference is to have good tents, because I expect them to fail at dark:30 in the middle of the night in high winds when I can't take the tent down and put up another one.

It gets to be a judgment call on whether you want to pay high price for premium goods or buy cheap stuff and lots of it for back ups. (We always have backups, though - even for expensive tents.) Some stuff we choose to buy lots of cheap items, some we choose to buy a couple of expensive things. People disagree on different items, and I always learn from listening to those that have different judgments from mine.

*Water bottles don't hold enough water. My current waterpack is 3 liters, and I drink it all in a morning, and much of in in the afternoon. I used to do shifts flagging on the highway after the event, 6 hours from 11:00 am so it was the heat of the day. I'd bring my 3-liter pack and a 2-liter pack and have consumed all the water by the end of the shift.