Well -- I can tell you what I've seen and heard. I had one for awhile but never used it - and haven't gotten a new one. But veggies don't take too long -- you may want to research it on the web, like maybe:
www.cookinglight.com www.marthastewart.com www.foodtv.com or other places of cooking resources. And all kinds of veggies will work - just depends on what you like!
But you can stir fry them in stock (veggie, chicken, etc. - just watch the sodium content) and get them more flavorful. And if can cut the veggies about the same size, they should take similar times. It's a bit like boiling veggies, that you really just have to taste it yourself to know. A bit general, but I saw that no one answered yet, so I thought I'd make a stab at it!
Good luck!
MD