No, it's ok. I realized that my original comment might not have been very clear. Now I'm probably going to ramble a bit and say stuff you already know since the answer to your question is so subjective.
The basic specs of the bar you posted are fine, it's bound to make a lot of light, probably more than both your headlights from that single bar. What you want though is entirely up to your needs. But, let's look at this as this bar making roughly 1.25 times the useable light of your headlamp, and most of it will be a near field flood lamp. (just a note, a 55watt HID will emit around 3500 lumens, a 55watt halogen around 1000, and I'm going with the assumption these LEDs make 2000)
Essentially, given the design of the beam pattern of a headlight, you have almost tripled your near field lighting, since your headlamp is made to project some light far away. But, the amount of light from a headlight is designed only to make it so you can see on what should be fairly straight, obstacle free roads, but cut off at a point where it would harm other driver's ability to see. So, as we all know, they aren't going to give you enough for off-road use, because you need to be able to see obstacles. So, people add off-road lights. Now, we could probably estimate the light output of a 55w halogen Hella as roughly 1000 lumens. So this one bar would be worth two of them. Plus, it is at a color temp closer to daylight, so it is closer to a full-spectrum light, meaning you will be able to see more of the colors of the objects the light is being reflected off. This means, even though you have the light of two of those Hellas, you are seeing more than what you can with two. Make sense?
But, on to the question of how much light do you want... Well, once again, that is dependent on your own needs. Basically what kind of terrain are you expecting, and what kind of speeds do you want to go through it. You know what it is like to overdrive your headlights right? Same issue here. You need enough light to be able to see the obstacle in enough time to react to it. But, you can go too far with this. If you are going through terrain where there are a lot of obstacles, and you are making too much light, you are going to blind yourself to anything beyond what is really close to you.
I guess if I were to make a suggestion, I would suggest buying some of the cheapest lights you can find at walmart or harbor freight or something, and seeing for yourself how much light you need. The nice thing about a halogen bulb is that 55 watts makes roughly the same amount of light no matter what, so one can estimate what you need. Though, you will likely need a lot less than you would get from the cheapie stuff, since they are going to do unsavory things with the photons the light emits into their junk reflectors. As to the light you posted, I want to reiterate, the output and the wattage are not really what I see a potential issue with. What I'm saying is that, looking at the pictures, I have doubts that there is enough surface area to dissipate the heat from those LEDs. You can find other LED bars for cheap, albeit maybe not that cheap, but still cheap. To a point, you are getting what you paid for. Aluminum, LEDs and electronics have a bare minimum price. If you are going too cheap with things, you know they cut back somewhere. For instance, they may be using LEDs that are made for a lower power application and overdriving them, or it may be a matter of cutting their costs by using less materials to make the cases. In this case, I suspect both.
