Picking a well-tolerated opiate is usually a 'hit or miss' process. The differences in tolerability come from several factors. For example, for some opiates, the administered medication is a 'prodrug' that must be converted to the active drug by the liver; an example is the conversion of codeine to morphine, which is more efficient in some people than in others. There is also wide variation in the degree of nausea produced by different medications in different people. I do not know of any evidence that hydromorphone is better tolerated overall than oxycodone.
There are a couple differences between medications that are worth noting; meperidine or Demerol should be avoided in the doses you are describing, as the primary breakdown product, normeperidine, is neurotoxic and causes seizures; Codeine is not a good choice at these doses as it just does not have that much potency; Morphine does tend to cause more stomach cramping and nausea, and is subject to high 'first pass metabolism' that makes oral dosing difficult; Any opiate at these doses should NOT contain acetominophen, aspirin, or ibuprofen (avoid percocet, for example).
Not part of your question, but you did not mention the source of your pain. You are on high doses of narcotics; If the pain is chronic and from a condition that does not reduce life expectancy, the use of opiates is at best controversial and at worst a potential disaster; I would encourage you to search for articles on 'nonmalignant chronic pain' and educate yourself to the risks and benefits. If, on the other hand, you are suffering a life-threatening condition such as cancer, there is no issue with opiate use, and I sincerely wish you the best.
I have a cronic back condition called spondolathesis spelling?? And I am looking for alternatives, my doc has just given me a lesser dose 20mg instead of the 80mg but I take it more often then the 80mg. He also gaev me percacet to help in between doses. I am still not completly sastiffied with this and I am looking for other options to discuss with him.