I use RDX500 and find that strung w/ leather grip, mine weigh about 12.7oz and 12.8oz; this can become cumbersome to add more weight. Especially since it seems like the racquet needs it swing speed for spin. My main problem is with loopy kick-serves, where I've noted better results w/ lighter/tween type frames. Hitting flat serves or topspin-slice serves seem to work w/ good pace and accuracy. Looking at the specs for the rqs-11, it looks like a perfect model for developing a serve-monster that isn't too heavy when you finish. Plus I like Hingis so it would be cool to have "her" frame The other thing, I want to decide on is whether to give the rdx500 more time vs. go for an rds002-tour (which is supposed to be a good serving stick, but wouldn't leave much room for customization). Thanks for any help or suggestions. I have done a search and seen a few posts on the rqs, but would like to hear from those who have actually added weight to their rqs-11 (or similar frame).