There will never be a clear cut answer based on gender. Because gender is a very personal preference. Some people, no matter what, prefer a specific gender. Based on experience, triggers, expectations, etc.

I would encourage awareness of any triggers. To think about "What would it be like to be with a male counselor?" Then, "What would it be like to be with a male?" Look for triggers or concerns about the actual gender (i.e.: I am a bit hesistant with a female because I have really negative experiences with my mother). Sometimes having to face the trigger in and of itself is a therapeutic need, which may sway you one way. Versus if you need to avoid that type of trigger which would sway you the other.

If there are no concerns/triggers that arise really thinking about the gender, then looking at other qualifications. What do you want the T to have training and experience in? What time of model do they use for treatment? etc.