It's not a good idea to mix opioids and benzos, mixing them is the leading cause of overdoses. They are both CNS depressants so they make each other stronger and increase the risks of passing out, stopping breathing, etc. If you are going to do it anyway, take less than half the dose of each drug that you would normally take - but I do not recommend mixing opioids and benzos at all.
Why do you mean by "how much of an opiate is this?" Tramadol is a synthetic opiate, which makes it an opioid. Are you trying to ask how the potency or effects compare to other opioids such as codeine or hydromorphone (Dilaudid)? Codeine and hydromorphone are not that similar to each other, hydromorphone is a lot stronger and is a semi-synthetic derivative of morphine. Codeine is weaker and is a natural opiate. Tramadol is stronger than codeine. I don't consider the high from tramadol and Dilaudid to be quite the same, (even when taking a lot of tramadol), but everyone's different I guess.
Tramadol is also different in that it is not solely an opioid but is also a serotonin releaser and norepinephrine reuptake inhibitor. Similar to some antidepressants. So it has those effects as well and if you take it too often there are terrible withdrawal symptoms.
