It depends on your personal outlook on it Kate. I personally would rather NOT have to make constant exchanges. Even though no one is/has given me a hard time about an exchange, I still don't like waiting on the first time it occurs because they think I did something "bad" to it or I replaced something too many times. I like knowing that when something fails(through normal use), I (still) have the ability to send it back and have it replaced (within a reasonable timeframe). But there are things I feel more comfortable doing with a $10 atomizer, as opposed to possibly damaging the EXPENSIVE one, and possibly having to justify my actions to get it replaced.
But I might be a bad example...So far, I've exchanged an Njoy atomizer and battery (both defective hardware, not bad through normal wear and tear), and I'm going to exchange a Janty atomizer that isn't performing well also (even after a cleaning that MAY not have been authorized by Janty). Overall, my atomizers and batteries seem to be holding up pretty well and I am not experiancing the issues that seem to be so common for others on the forum. Maybe I'm not using them as much, I'm just luckier, or it's all waiting to break at the same time. But so far, I'm pretty happy with it all. And I like the mix of what I have. I still want everything to be 99.999% dependable, but then...I also want to never have to pay taxes again too. Some things we just have to live with, and take advantage of what's available at the present.
I think the 1 year on the Njoy is...reasonable. 5 years on one of those (Sedansa?) I think may come to haunt the vendor, and at the current price point, I think the generic guarantee (14 days) is reasonable also (replaces DOA hardware essentially).