Test is a must as far as I am concerned.
I started with fina only. Was great fo about 4 weeks. Even increased my libido etc.. in the beginining. After about 4 weeks I could tell by my libido and energy levels that my test levels were dropping. I added the test at about 500mg a week and it was awesome. You won't lose the fat burning effect of tren but depending on what test you use, you will retain water so the fat loss may be less evident.
One thing I would say, is that all you guys who are still flying high, young, and with good natural testosterone production, Don't be too quick to jump into this stuff. It is not automatic that gear will give you the look (or BB success) you want. Once you start screwing with your endocrine system, it seems to me, that you are never sure if you are firing on all cylinders when off. It does really fuck with your body (I will never do a 6 month cycle again). Don't get me wrong, I love the shit BUT I do have a problem enjoying the gym when off.
Sorry for getting off on a tangent, just some points to ponder.