In the wave 8 Guri discussion thread, it was posited that Guri is a poor candidate for Push the limit since the starviper only has access to green one banks and straights up to speed 3. However, this is the exact same as the T-70, and everyone has proclaimed the brilliance of Push the limit there.
So I ask, what is the difference?
Sigh... This seems like you are just trolling now.
I'm not sure what you hate so much about PtL/BB-8 that you feel the need to constantly try to make a case it sucks. Whatever it is, let it go. Please.
I think there have been tons of reasons presented to your OP.
1) Ship Durability
2) Low PS
3) Loss of normal action
4) instability of Cloaking Device
5) Positional requirement of her ability
And I'll add:
6) Cost. The Guri you are talking about is easily over 40 points..
Guri + Virago + PtL + AdvSensors = 37 by itself, without cloaking, stygium, or Thrusters
Wedge + PtL + BB-8 = 34
7) One can have Biggs, the other can't.

