Phil,
I'm sure that most tool companies look to tolerance stack up and material properties, but that wasn't what I meant. As an example see the wrench photo I attached (not my photo). It's an open end wrench, and the profile on the "flats" of the wrench do actually make a difference. That's what I mean by design. My engineering background is mostly aerospace and forensics, so little things that don't matter to most suddenly become important details in my world. It is a level of detail that doesn't generally exist in bike tools because 1) It isn't really needed and 2) The majority of people would not want to pay for it anyways. Actually, the Park TS-3 is a perfect example of this. In most applications, it is, without question, a better tool than the TS-2, but the demand isn't there, and thus it isn't made any more.
1) A guy who does his wheels once every 5 years can do it in the frame.
2) A guy who does his wheels more often uses a cheap truing stand.
3) Someone who trues their wheels regularly, and some shops use a TS-2
4) A shop that does a LOT of wheels probably has a TS-3 (in my limited observations).
5) A place that does high end production looks like this: http://www.cyclingnews.com/features/...-wheel-factory

It all depends on what you need/want. What bothers me is when someone making tools for groups 1-2 claims the tools are the same as the ones for groups 3-5.

I will admit that I do not own any of your tools, nor have I used them. In this case, it looks like Operator has, and I'm inclined to trust his judgment in this case. My tools are combination of (mostly) Park, VAR, Craftsman, and Shimano (Cable cutters and some crank/shifter specific ones). They've served me well for the most part. I have a couple other oddball tools, the stupid Campy left hand thread crank puller, Pedro's plastic tire levers, etc. Ones that flat out don't work, like the Jagwire cable cutters (foolish purchase) get replaced. As it would be, none of my friends own your tools, none of the shops here stock them, and I'm not inclined to purchase a replacement tool when other than my floor pump I'm happy with my current tools. If I ever do stumble across them, I'll be happy to give you a review, I'm never short on opinions.
Edit: Since you linked to it, I'll throw in the following observations:
1) While it's pretty clear that you work for Filzer, posting a link to an Amazon store for your own product (I presume without being a site sponsor) is questionable. While still questionable, perhaps a link to your site page rather than a sales page would be more appropriate:
http://www.filzer.com/products.php?id=129
2) It looks a bit short, although without a listed length I'm only speculating.
3) It also looks like it has a flat handle. Personally, I don't like having to put a rag around a wrench handle to save my hand with particularly stubborn pedals. A longer and/or rounded handle makes a big difference. As far as I know, the pedal wrench is one of the only wrenches (maybe the only) which Park takes the trouble of putting a wider handle on. There's a reason for this.
4) I don't know about the tolerance or fit as I don't have one in my hand. It looks like it would be fine for limited home use (so is a cheap 15mm and a rag), but it doesn't look like something I'd want to use all day.