It should be noted that both limbs had limb savers attached, which are included in the weight measurements. There was a slight difference in brace height for the Quattro which should only have a small impact on the results.
(Correction: Both were 73% efficient. There was a overwrite in my program. Charts have been fixed) The F7 were the more efficient limb at 81% compared to 77% for the Quattro. However, both numbers are very high for my measurement method. While the Quattro stored more energy, and were faster, the F7 were more efficient. This efficiency advantage appears to be a consequence of the smoothness at the end of draw where the F7 flatten out at about 2.2 pounds per inch from 29 to 32 inches, compared to the Quattro that start to stack after 27 inches.
The energy per weight on the fingers is pretty similar for both limbs, neither breaking 1.0 until 32 inches.
The Quattro were faster at 199 fps and also had lighter limb tips at 80 gr using the two scale measuring method. This is compared to 195 and 86 for the F7.
The smoothness curves is where it gets interesting. The Quattro have a remarkably flat first derivative (smoothness) curve from about 18 inches to 27 inches. This is unique profile for conventional recurve limbs that I have measured. After 27, they start to stack, which is quite early in the draw cycle. The F7 do not stack all the way out to 33 inches. As mentioned before, they run about 2.2 pounds/inch from 29 to 32.
There is a clear difference between the limbs. The F7 are smooth at the end of the draw, while the Quattro are smooth during a large portion of the draw prior to release. The smoothness curves cross at 29 inches, after which, the F7 pull less pounds per inch of draw. So the choice is between a smoother more efficient limb, or a slightly faster but less smooth limb. You might be able to up the weight on the F7, maintain a similar holding weight at full draw, and match the speed of the Quattro, while maintaining the smoothness of the F7. It would be interesting to try that out.
Thanks to Gary McCain for making his bows available to me to test.