I haven't heard of any. The Jasper is supposed to be mostly defect-free. It's supposed to run at a lower temperature due to a lower voltage power supply, and the RROD problem is commonly attributed to overheating. However you might also want to search for reports of E74 errors which may or may not have anything to do with the voltage/amp or overheating problems. My own older model 360 (not a Jasper) suffered an E74, rendering it useless until Microsoft could send me a "new" refurbished unit. The refurbished unit they sent me, of course, was neither a Falcon or a Jasper, but rather another failure-prone older model. Thanks a lot, Microsoft. Guess I'll be sending that one back before too long also.
But yeah, I haven't heard of any Jaspers getting the RROD, but that's not the only error you have to worry about. E74 has actually surpassed RROD as the #1 reported Xbox360 problem, so make sure to look that up too. It has something to do with the graphics card failing, I believe. In my opinion, you'd be better off just getting a PS3 -- but, that's just my opinion.
If you absolutely must have Microsoft's failware, make sure it is a true Jasper. Just because it's "new" and on the shelf now, does not mean it hasn't been sitting on the shelf or in a back room or warehouse somewhere for the past couple of years. Check the bar code on the unit, it should be visible through a hole in the original packaging (for scanning purposes). Look for the voltage reading right above where it says "Made In China" (is anyone really surprised that it's made in China?). It should say 12V, followed by 12,1A. This is a Jasper model. If it says 12V, 14,2A, it is a Falcon model -- less failure prone than my own 16,5A piece of crap (most likely a Zephyr model), but not as good as the Jasper. Another way to identify it would be to simply check the manufacture date. Supposedly units made after August of 2008 are Jasper units. They may also have the Valhalla version out now too, though I'm not sure how to identify it. I'm assuming the Valhalla will be similar to or better than the Jasper units, and with any luck will be mostly failure-free.