If you don't have an opiate tolerance, 100mg might have you feeling pretty good. Tramadol is hit or miss, some people like it and others don't. For years people did nothing but talk trash about tramadol on bluelight. Many people who never even tried the drug would preach about how it was just garbage and you should just throw it away. This is due to a few knowledgeable people on this board with massive opiate tolerances trying tramadol and not getting anything from the drug. I guess they never really stopped to think that the average non-tolerant user might be able to get high from tramadol.
Personally I was introduced to tramadol by a good friend of mine who was an extremely smart chemist (may he rest in peace

). I had been clean from opiates for almost a year and I had a great experience from just 100mg of tramadol powder. Since then, I've been spreading the word that tramadol isn't all bad and is worth trying at least. If you have a massive opiate tolerance you can't expect much from it, but it can be useful for the non-tolerant user or for potentiating other opiates. Just be careful, if you take too much (400mg or so) you can experience a seizure.
Also, the combo of benzos + tramadol feels really good. tramadol + valium is my favorite tramadol combo, my friend labeled this combo "tramalium" (patent pending

). As always, be careful when mixing CNS depressants, but tramadol isn't a very strong CNS depressant.
Hopefully you'll like it. Have fun.