in regards to serve returns, is a open(ex. 16x19) or a closed (ex.18x20) better for serve returns? same question goes for head size (mid, midsize, oversize or doesn't matter) also, can the flexibilty of the racquet effect the return? does anyone have any suggestion for stable/solid racquets for me to demo, or can recommend some way to make a racquet more stable? also, i'm a 3.5 player, with a non-attacking game (counterpuncher) who goes to net on short balls. i'm hoping to play for my college team this year, and hopefully in 6 months, i can make a transition from 3.5 to 4.0, or at least be close to it.