Whoa - the 604 EF’s! Are they worth it? 
For most people, the answer is no.
At $1000 per box (current bid), there are less expensive vintage nibs that will produce excellent work. These nibs require a very light touch, which not everyone has.
For collectors, they might buy one or a few, but not a whole box (at least I know of no collector that buys each type of nib by the box just to have a box full). For users (vs. collectors), most will buy a few to try, but prefer the cost of good modern nibs if they are expecting to use many of them over a long period of time, or find the nib doesn't suit their touch.
One group that might buy them at this price or higher are dealers, who would break the box and try to sell them a few at a time, say at double the price, say $15 or even more, on eBay. That's a slow process. I've followed a couple of dealers over time that do this, and it's a long process.
There is one group that might also buy at this level and quantity--those that use this nib often as their main nib and plan to use it for the long term. I would be one of this group, although I don't know of anyone else specifically that uses this nib day in day out. Surely there must be a few. But take it from me, a great nib does not make a great penman. For someone to get the most out of the nib, it would probably require using a hundred or more to just to acquire the skill to use it to its potential.
It must be noted, though, these don't come up for sale by the box very often. So, if you're willing to make a big commitment to one nib, here's your chance.
Chris Yoke wrote an article some years ago about buying nibs, and he felt at the time no nib was worth more than $5. Perhaps that number has gone up with time, but the market will tell what the worth really is, at least to someone who buys it.
Update: With 1 day, 18 hrs. to go, the bid is $1488--$10.33 per nib.
