A few comments on this whole process which I know all to well.....
DK/Mouser/Farnell aren't the be-all & end-all of component suppliers. Franchised specialist distis can often be significantly cheaper once you get into the 100+ or full reel/tray quantities. They are typically a bit less easy to deal with, and you often get a better price if you phone them up than online. You also often get this "Target Price" bullshit to which I always answer "As cheap as possible". They tend to also add delivery charges and refuse to use anything but UPS/Fedex etc. however savings can be significant enough to justify the hassle.
DK has about the best parametric search but still falls down occasionally, an example being input voltage range on regulators, where it needs a 'min' and a 'max' input rather than seperately listing all the different ranges. the way they list the same part multiple times for different tape/reel options also produces an unnecessarily large number of search results.
Farnell's parametric search is much poorer due to bad/inconsistent data entry, e.g. you get seperate entries for "5V, 5v, 5.00VDC" etc. The data has obviously been entered by people who don't understand what the figures mean so you frequently need to do multiple selections to avoid missing things. And then you still often miss things due to strangeness in the way they've been categorized.
What they have ALL so far failed to implement is a way to specify the quantity at which you want to sort by price. Diferent manufacturers (who often are the ones dictating the price breaks) have different, sometimes vastly different qty/price functions, so the ability to sort by 100x price would be somewhat useful if ou are looking to buy 100 parts.
And don't get me started on buying FPGAs - what's all this "Supported price" bollocks all about.. I just wanna buy the goddamn things not jump through a load of hoops created by some marketing dickhead.