Those batteries suck but they are a decent bang for the buck. Most likely won't blow up your phone though. I've put them through the washer and gas dryer tons of time and punctured them by accident.
If you want a known good, get an Anker. A bit pricier but you know what you're getting. There may be diamonds in the rough with the cheaper ones but it's hard to say for sure unless you want to get a bunch of different ones and test. There's a good thread on XDA for HTC Sensation batteries where someone is testing tons of third party batteries for true capacity.
No, you most likely won't find any third party batteries with temperature sensors. The Mugens might have it, but I'm not certain. Definitely not worth the money though.
How long have you had your Triumph? Call Virgin Mobile. They should be able to send you a new one no questions asked, free shipping and all. If you really wanted to push it, they might even overnight it (although every time they claimed to overnight, it still came via 3 day or ground)
