Roseville Modern Stoneware and my dishwasher  

Lovely stuff. Go ahead and use it.
Hand wash the serving and rare pieces, but everyday use will eventually take a toll on the oft-used items as much as putting them in an automatic dishwasher will. Continue to pick up replacements for things like plates and bowls that receive the most wear and keep them in stock for entertaining and so that you won't overly despair when accidents happen.

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Thanks guys! Great advice. ...
Thanks guys! Great advice. And what I wanted to hear, so that's doubly nice 🙂
Love that dinnerware Tom Ado - I've seen a piece or two of that here and there before, but never a full set! Impressive (and fun to use, I'm sure)!

If it were Russel Wright by Steubenville,
I might advise otherwise, as I've seen plenty with crackled glazes. I used the "Iroquois" line for years and years when my kids were young with hardly a care, but that stuff is nearly bullet-proof and fairly easily replaced.
If you're at all hesitant, you could deselect the "sanitize" and/or drying functions on your washer, if able, to reduce exposure to higher temperatures. Many dishwasher detergents are very harsh and contain bleach, so it's probably a good idea to inspect your treasures closely to make sure there's no harm done from repeated cycles.
Again, though, you have some nice things there. I don't blame you for wanting to be careful with them.
Oh, yeah. One more thing. I'd keep it out of the microwave!

Thanks tktoo! Iroquois...
Thanks tktoo! Iroquois Casual's my current dinnerware actually - love the color palette on that one. I've only got a small set of it, but I've definitely enjoyed it's durability. I was planning to get rid of it actually (for the sake of simplicity and cupboard space), but your note about it being suitable for children may be argument enough to convince my girlfriend that we should keep it 🙂 I'll keep adding to it, as I find it on the cheap.
Thanks again for your input!