TBol is absolutely incredible. But you also need to recognize what you will have to deal with while using one of them. Var is much safer on the liver than TBol, but TBol I feel will make you very happy.
Concerning liver toxicity, yes Anavar is a C17 modified substance, but it has actually been proven to be FAR safer for your liver than other C17 substances. Understand this is what makes it so the substance isn't deactivated when it passes through the liver. That said however, Anavar has been proven to cause far less stress on your liver. Its not as extensively metabolized by the liver as other orals with the same alteration. Furthermore, tests conducted have proven that even 1/3+ of the Anavar is STILL active by the time you piss it out. Tests have actually confirmed it causes the absolute least amount of liver stress than any other oral tested (which all were C17 modified from my understanding). In the test, it actually produced something like 75% less BSP than equal doses of the other compounds.
Something else interesting is when tests were performed on men suffering from AIDS taking Anavar, the tests actually proved there were no extreme signs of it causes liver stress. Ultimately it is far safer obviously. About 15% of the individuals at 80MG/day were documented at grade 3 and 4 toxicity according to AST and ALT. Compare this with any other oral substance modified the same, and that's fucking BEANS.