Servomyces vs. Wyeast Nutrient vs. Generic

I was milling over the assorted yeast nutrients available to home brewers, and am wondering if any one in particular has a distinct advantage. White Labs Servomyces is by far the most expensive, and has the most elaborate description attached to it (developed in Munich, etc etc etc). The Wyeast nutrient seems to offer everything that one can get from Servomyces (primarily zinc and amino acids), but is literally pennies on the dollar in comparison ($10 for six doses vs. $2.25 for 20+ doses). Then there's diammonium phosphate (ie: generic), which is half the price of Wyeast.

Do any of these offer distinct advantages or disadvantages when compared to one another? In my brews, I've been using the Wyeast blend to good effect, but am curious to hear how the various offerings stack up.

Bulk DAP is something like $300 a ton. Bulk urea about the same. The money they charge for "yeast nutrient" packages is highway robbery.

Permit me to be skeptical of the claims for high buck nutrient packs.

Yeah, I hear what you're saying. The Wyeast one seems fairly well rounded, with amino acids, zinc, etc, and at the end of the day it's not a huge premium over the DAP + Urea mixes out there, so that's what I'm going to go with, I suppose.

Although White Labs has some strains that I really love, I have a sinking feeling that their über-expensive capsules amount to nothing more than a blend similar to Wyeast nutrient in gel-cap form. Truth be told, I prefer the loose stuff anyway.

I've never used servomyces, nor have I used the wyeast brand of nutrient. I've used fermaid, the generic nutrient & energizer from my LHBS, and generic/bulk DAP. I honestly haven't noticed any difference between the generic/bulk stuff & the brand name stuff.

So, servomyces is just yeast that was grown in a nutrient rich environment according to White Labs' site. So, why not just buy a tub of pure brewer's yeast from the store (in the vitamins section) and use that?