I cannot pretend to know your particular industry, but I am addressing the general attitude that if something is newer or flashier, it must be better. Sometimes it is. But too often the extra flash is useless for common applications, and people trying to replace the old with the new ignore the fact that a lot more thought may have gone into the old, making it more useful despite the earlier technology. It is too easy to assume that moving forward in time necessarily means moving forward in efficiency or some other virtue. Here are some examples.
I might appeal on the basis of much of what highly respected electronic industry guru and lecturer Bob Pease keeps pointing out in his columns in Electronic Design magazine. For example, he has had a series on fuzzy logic. In one early article in the series he tells how fuzzy-logic proponents used a '486 computer to demonstrate "the wonders" of fuzzy logic in a type of controller. Then he shows how you could do the same control job with a $0.23 quad op amp and a few discreets on a smaller board-- kind of humiliating for those who thought they were announcing a new and better solution, the wave of the future! (And yes, he breadboarded it to prove his point.) After the fourth article in the series, he sent the material to several fuzzy-logic experts with the challenge to show where he was wrong, if anywhere. The challenge was also published, but there have been no takers. And where is fuzzy logic today?
He has another series on PSpice, pointing out how easily people let it mislead them because they use it as a substitute for thinking instead of as just a tool and recognizing its shortcomings. He gives many true stories as examples. He laments that universities are mostly using computer simulation and teaching very little hands-on methodology, and that as a result, the graduates are not prepared for real-world design challenges. (They should be teaching both.)
He lectures all over the world, using an overhead projector instead of PowerPoint. This allows him to quickly draw or mark on diagrams as he answers questions from the audience. Is he against innovation? Of course not. He designs analog ICs at National Semiconductor-- the ICs your cell phone, new car, and DVD player rely on.
I'm on the board of a school with preschool through 8th grade. The superintendent has some kind of love afair with PCs and is trying to put them everywhere. One question I have brought up that we still don't have answers to is why did the accounting job take fewer people and less office space 25 years ago with no computers than it does today with modern PCs, a server, and all the modern software? (And no, there's not much difference in the size of the school.)
In my work I frequently lay out extremely dense, 12-layer printed circuit boards. I use a cheap, old CAD that runs under DOS. Its bugs are few and minor, and unlike other CADs I've tried, it doesn't try to tell me I can't do this or that just because it doesn't understand our unconventional but very successful methods of packing more parts in less space. This old CAD has always done the job quite well, so there has been no reason to update it. Our competitors with their newer tools have not been able to catch us.
That brings me back to these "canned-solution" products. A manufacturer may tout a long list of wonderful things the product can do; but if it's not flexible enough to let you do the things the designers didn't think of, you're out of luck. If the older technology provides a way to do the job, even if it's less efficient than the newer technology would be if it didn't lock you out, I'll take the old.
I remember looking at the adds for the first hand-held computers that were supposed to be able to recognize handwriting. The technology required to do that seemed absolutely amazing; but I also thought, "How dumb! Someone has forgotten that one reason we used typewriters before there were computers was that typing was faster than handwriting-- a _lot_ faster!" It's another example of innovation that was not an improvement. As it turned out, the Apple Newton's poor recognition of handwriting was quite a disappointment anyway.
Even though my 71 with its modules and the ton of LEX files from the user groups is far more powerful than my 41cx, I seldom use the 71. I'm glad to have it when I need it, but the 41 is more practical as a calculator. What would be on my wish list for a better 41 is greater speed and memory to make Forth and other high-level languages practical. Graphics and color are not on my wish list. If I want a bigger text display, I connect the 80-column video monitor; but the last time I did that was years ago.
I hold onto the old HPs not because of nostalgia like the old picture, but because of flexibility, interfaceability, expandability, and so on. They have no dependence on here-today-gone-tomorrow PCs or PC software either.
It may be appropriate to have both the HP and the IPaq in your arsenal.