It really depends on how much load you are putting on it. I would never buy one personally but if you keep the load at under 70% of it's rated capacity I don't think you'll run into any problems. Kind of like buying an economy car, if you don't run the sh!t out of it then it's fine as a daily driver... if you are going to race it then chances are somethings going to blow.
Ultra's are not known as a good maker, no offence to those out there that own one but really, the good reviews come from those that don't know better or that only load them to 50% max so the chances of it having problems are low.
It also depends on what you are going to run on it.... doesn't make sense to use it for a QX6800, two 8800GTX's, two raptors, a x-fi fatality and water cooling as you've just spent $3000 on the rest of the computer... would you really want to chance all that investment on a $70 psu? On the other hand, for a E6300, 7600gt... etc (under $1000) then it's not so much of a risk, both in terms of less stress on the psu and less loss if something blows.