Exactly my point
, although not the best example...
guanako, the point is not to choose the fanciest one with the most options for the same price. But the point is that often (not always) the higher you go in wattage, the more quality is build in... But IMHO, the example just shows the opposite though. Nevertheless this is actually a good thing as it is a nice example of how "bigger" PSU's can also be bad.
Thus, as for me, personally, I would never buy that 480W one in that price range from that company.
In that price range I wouldn't be surprised at all if that "simple" 300W one is actual far better quality in the long run and much more solid than the fancy 480W.
Because for the cheap price of the 480W they had to put in all the fancy stuff. Compare this to the normal price of the 300W. Because they have far less fancy stuff, they could invest in better quality components. And because it is much simpler it is far more solid.
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Remember that, when the price looks cheap, it quite often is cheap quality also...
This can also be "somewhat" tested by yourself in the store, although it also needs some practice. A decent power supply relativly weights a lot! If it seems like it weights almost nothing, leave it immediatly and buy another...
Cheap components means stripping down on stuff. True you can get 400W out of something very small. But the question is for how long? This also often goes hand in hand with how much heat the PSU produces (but you can't test this in the store of course). The more heat, the less quality. And since PC's are often ditched for a new one every 6 months on average and since many people like flashing lights and many big fans, companies often strip down on their quality components since it will be of no use anyways for the average user's PC lifetime and/or people like those big fans on the PSU, which often actually are also needed because it will heat up a lot because of the low quality of components.
Also, despite new technology, for a PSU, the smaller doesn't not mean the better. In fact it is the opposite for a PSU: the bigger and heavier it is the better (again comparing same classed PSU's with same wattages here)!.
An comparisson example I'd always like to use are batteries (and my car again 
). A car battery of 12V is much more robust, has a much longer lifetime (even without the accumulator connected to charge it), much more steady output and can take much more load than a small 12V battery for some toy racing car... And if you think this comparisson is a bit unfair, then compare an AA battery with a smaller AAA battery. The smaller one has a far less lifetime because it can't take as much load over time, despite they provide the same voltage and thus the same power.
In short: simply invest in an equaly or higher "wattage"'d PSU than the one you had (but as D:Frag rightfully suggests, from a different brand), which is normally priced for its class range. A simple looking but decent PSU... And avoid the cheap "to good to be true" budget PSU's...
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