Do you think this will affect flavor?
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If you mean the choice of light/xl/pils DME + steeped/partial mashed grain vs. using amber and dark DME, then I say only to look at any All Grain recipe here. You'll see that you only need a small amount of specialty grains and a majority of base malt -- so just use your light DME as a sub for base malt and steep/partial mash the specialties for greatest control and authenticity (as opposed to guessing the specialty malt content and character of generically specialty malted amber, and dark DMEs).
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If you're instead referring to the choice of pilsen vs. light or x-light DME as a substitute for the base malt in traditional all-grain recipes . . . Well, yea, that will affect flavor a bit too.
A look at other similar threads seems to conclude that if you are going the extract and steep route and going for as much authenticity as possible, then you'd want to use pilsen DME for recipes that call for pilsen malt, and light/xl DME for those calling for plain old 2-row (breiss for american and munton's for british, if you wanna get pickier). This makes sense because Briess Pilsen DME is made from pilsen malt and some carapils, whereas their light (called "golden light") is made from "base malt" (american 2-row, no doubt) and some carapils.
I personally can only justify buying one 50# bag at this point, and I do like me some saisons and tripels, both of which will benefit from the lighter color (and traditionally use pils), so I'm going with the pilsen and using it for my American IPAs as well, adding some steeped crystal (which i'd do with the light stuff anyway).
I suppose that if you knew you weren't doing any super light pilsen beers, and you specifically were looking for british or american 2-row extract, then you might pay a little extra for the DME that best suits your brews. I question how much it matters though in darker brews where a higher amount of the malt flavor and color is coming from the specialty grains anyway.
$2.31/# is plenty of reason for me personally to pick the one DME and adapt with specialty grains!