I don't know how much it will help, but the Comfort Hybrid grip on the Wilson Juice 108 might make it a bit easier on the arm than the 100 or Pro versions of the Juice. You might add some lead tape to make it a bit heavier and subdue the frame shock even more.
Here is an interesting piece on flex/stiffness ratings Tennis Express:
Flex: While flex sounds like it should be an easy to understand, it is slightly more complicated than the simple number that we or anyone else lists for flex. The unfortunate truth is that given current testing equipment designed for use on racquets, the flex is only measured at one point along the length of the racquet, that being the throat. While this can give a rough estimate for some frames, it does a disservice because many of the material compositions of frames today alter the stiffness based on the location along the racquet to serve specific purposes. A famous example of this would be tapered beam sections of the Wilson Hammer line of racquets. By making the beam width thinner in the throat area, it offered a softer flex when measured, but the much thicker hoop area of the frame was also significantly stiffer, which could not be easily measured. As expected, the stiffer a frame is, the harsher it is on the arm.
This is for two reasons: shock and vibration. It is important to realize that these are different aspects and they affect the body in slightly different ways. Shock is most often associated with hitting off center, as an extremely harsh torque felt especially in the hand, wrist, and elbow. This also occurs on shots hit in the sweet spot, but the energy absorption and repulsion of the strings do mitigate some of the impact forces, so the feeling is not as severe. Vibration on the other hand, is the residual waves of frequency that radiate down the frame and into the arm. This is typically not felt by the player on the court, and will usually only result in soreness after the fact, but can be enough to also cause problems. Most often this vibration is the result of a frame being too light that it is not able to dampen the incoming frequency of waves, but can occurs in heavier frames as well. Interestingly, shock is typically associated with stiffer frames, while vibrational damage is more likely in more flexible frames. While the more flexible frame will typically dampen the amplitude, or strength of the wave, depending on the frequency, it can still cause major problems to a players arm.
For this reason, when it comes to flex, the idea is to look for something that is relatively low in flex, but as frames become more flexible they tend to lose some of their stability. This, in addition to various technologies designed to alleviate tennis elbow, makes it difficult to judge a frame based on only one isolated flex measurement. For this reason, we suggest that you do not take the flex rating as an “end all” searching solution, but instead focus on it as a piece to a much more complicated puzzle.
Last edited by SystemicAnomaly; 10-05-2012 at 05:45 AM.