Hi,
personaly I use ff.net figures on TTC or diamond bases
the stance of line ff.net players is very low and forward, and the arms are often wide too. It's working great.
The only issue is if you add too much details on the ff.net figures (details, muscles sculpted with putty, modelling flock on figure plateform), you can easily reach the 3.0grams limit.
THe solution is to use a bigger weight limit (personaly I use 3.2grams for linemen, 3.0grams for all the other players), or reduce the plateform size (Franny Jboy do that), or even swap the original plateform for a lighter one (thin plasticard, for example).