Havent had experience with those pads. But basically i was experiencing the same feeling (as you) with my Nissan S15 4pots. I then did a full overhaul, serviced the calipers (weren't in good condition), changed brakepads (RS pads from Automotive Genesis) and a set of stainless-steel braided brakehoses.

Now brake pedal feels very firm and the bite/force is what i expect from a 4pot. 

Hope it helps.

i also dunno one leh... no reference to refer to... no one to ask...
the other day my mirage calipers jammed... no choice have to remove it myself and check whats the problem.... buta2 in the end manage to clean up everything and fixed it back properly... now running vr nicely with no leaks...  

noler.... thats brake fluid flushing only...

servicing calipers include removing the whole caliper unit... taking apart the piston off the calipers... cleaning up all the dust and dirt inside and replacing all the rubber seals... fit back everything... top up the brake fluid and do brake bleeding...