So I have a lens decision to make. Now before you immediately say 24-70, hear me out. I have a D90 and Im looking for a good mid-range zoom to be a general use, everyday lens. I previously owned a Tamron 28-75, but the focus was just horrendous in any amount of indoors light and it would produce a really sharp nice image one moment and a really out of focus crappy one the next moment (and no it was not just camera shake). But I have loved the 50mm prime, when I had my d60 I manual focused the 50 more than I would even try to use the Tamron, so now im in the market for some nice Nikon glass. Ive decided against the 17-55 after talking to a bunch of people. My friends father has a 24-85 f2.8-4 and it does a great job on their d2x, however I haven't taken a whole ton of pictures with it, just a couple random ones around the house. I have been selling a bunch of things and trying to save up for the coveted Nikon 24-70, but now I am having second thoughts. I am by no means a professional, do I really need a 1700 lens? The 24-85 is 700, and with the current money I have from selling things I could purchase that and an sb600 (I really need a flash). Or should I stay on track, and save for the more expensive way better (almost perfect) lens that will last me for a long time, but would make me go bankrupt, or do I go for the lesser lens that will produce images good enough for an amateur who only posts images on the internet. My hangups for the 24-85 are that it would mostly be at f3.5-4 rather than 2.8, but is that a huge deal with good iso processing associated with the d90 (eventhough shooting high iso is always not recommended)? Ive also heard that auto focus is slow in low light (something that really bothered me with the tamron), is that the lens or the body since it focuses with the in body motor? My only apprehensions about the 24-70 is obviously just the price. If anyone made it through reading all of this, any help would be incredibly helpful, and if you have any other suggestions let me know.