Tough call. Morphine has a very low BA of about 30% but some people absolutely love it. Oxycodone has a BA of close to 100%. (Around 80 to 90% per the professionals but I take it and think it's closer to 100%).
Look around the site or search for morphine and see what you think. We all have different opinions but I was put on morphine at my pain clinic and went back 2 weeks later in terrible pain so I was switched to oxycodone and it was a miracle worker for me.
I've been on it 8 years and still wouldn't trade it.
Also there's tons of debating and anecdotal threads on this subject through the search engine. Or you can use Google to ask your question and "site:Bluelight.org", threads will abound.