I agree with David (though have less experience comparing than he), but if one is looking for a "decent" tripod which is priced well below Gitzo, then Benro is worth a look IMO. I have and prefer Gitzo, but I also have one Benro tripod and it does fine too. I know the strengths of the Gitzos and the weakness of the Benros, so have no problem using either when appropriate. One can adapt. But to be clear, I do not feel that the Benro are weak if appropriately sized to the kit.
I own a Benro because it was the best available when I was looking for a tripod in southeast Asia for a project. I may have been able to find a very over-priced Gitzo if I had looked harder, and I did find over-priced Manfroto models, but the Benro offered more value. Clearly, I prefer my Gitzos, but I have no disrespect for the Benro in terms of support for my DSLR kit. I don't have a model appropriate for my medium format kit, so strength, as I use it, isn't an issue.
As for "knock-off": yeah, probably. But let's be honest... there are three legs and a mounting point. The Benro has a different grip on the leg-locks, a compass (whooo-hoooo) and a sling mount. No decoder ring though.
And actually, Benro had minor design improvements prior to Gitzo WRT to leg-span-cog adjustments, etc. The added pressure is likely good in that it keeps Gitzo from resting on their laurels.
In my opinion, Gitzo is the best for most applications, but if one can not afford or justify a Gitzo, then they could do worse than Benro or Induro. Frankly, from what I've seen, I feel Induro is an over-priced version of Benros, so I'd look to Benro before Induro.
Just my 2¢