Too much
The Pacific Laser is smaller and lighter than the other (so called) 120 sized aerobats. It will fly the IMAC advanced pattern with a 91. It will weigh between 8 and 9 pounds ready to fly.
The 120 four stroke will give it unlimited verticle from a hover, as will the 108. The 160 will be too big (prop will stick out too far from the front of the cowl) and heavy (you'll need a lot of tail weight, even with the servos back there).
BTW, there is a review in the current (July) issue of RCM.
Jim