They are both mild on the hair. Anavar is probably the most mild but OT is a good choice also.
OT (Tbol) has a very low androgenic profile. It isnt derived from DHT and doesnt convert to DHT from what I've read.
You would get a lot more "bang for your buck" with OT. A lot of people have abandoned Var in favor of OT. You get better gains with almost no sides and a cheaper price.