The difference between 17 and 24 mm may seem small, but it translates to a huge difference in real life. Photography isn't all about math, and it's difficult to express what you see through the viewfinder using mathematical formulae. There is a reason why people don't recommend a 24-70 on an APS-C camera simply because it wasn't meant for an APS-C camera. 3m is a LOT of distance in real-world terms, especially indoors. The 18-50 was designed such that it would give an "ideal" range that approximates the 24-70 in full-frame terms. I still maintain that the only reason why anyone would get a 24-70 is because of the possibility of getting a full-frame camera in the near future.
And remember, scores on review sites are basically an ambiguous collection of numbers by people who are giving a subjective opinion. The 24-70 is no doubt a fantastic lens, but you have to see it in the proper context.
Of course, I could very well be accused of being pedantic and someone else could come along and say, "Rubbish! Who says 24-70 is no good for APS-C sensors? I use it on my camera and I love it!"
Ultimately, it's your call.