Trying to deceide which to ad to my bag. In the last month it has become very noticable a need for a 3rd game ball. I currently use the Forza out of my bag for the first two games. In the last month I have been rolling a lot more consistent. The problem I am having is lossing carry very end of second game into the 3rd game. I am going from about 1 or 2 7 pins in each of the first two game to a 5-6 average the last game. 

I don't know all my stats that well but know I am left handed at about 13 mph with I would guess 250-300 rpm. My comfort zone line is playing about 20 at the line 13 at the arrow and 7 at the break point. I believe that the Forza is facing a little early late in the set and no longer has the energy to carry the corners. I try to adjust and see a mix bag of wrapping it to being flat. Or if I adjust to much I will leave the 10 instead of the 7 or even pocket 7-10 splits.I would be happy to hear any suggestions.

beeks has it nailed pretty good.

If you are more adept at moving inside use the Burn.  If you like to stay further outside use an Ascent Apex.  13 mph at the backend?

In this same situation on the right side I normally use a Venom Shock P-I-R 4.25" pin to PAP for the fresh and ball down to a Venom Panic pin above 4.50" pin to PAP (drilled this week).