I am thinking about getting a Jackson. I used to have Veiled but it died during the winter because my house got too cold but that won't be a problem now. My question is how does a Jackson compare to a Veiled?
Well for one thing, Jackson's need a lower temperature range than Veileds, so that might work in your favour.
But they also need quite a bit more humidity.
I've never kept a Jackson's, so I can't answer your question fully, but perhaps you should check out this site: Jackson's Chameleon Information
Veileds in the wild have been know to survive freezing temperatures. Not that this is something you really want to do to a captive animal but I think you should look again at what your husbandry was with the veiled. The veileds that come from the mountains have very similar enviroments to a Jacksons. If there was a flaw in your husbandry it will need to be corrected or more thought out Jackson chameleons are way more sensetive to mismanagement then a veiled would be.