The Fischer racquet is indeed easy on the arm, but have you considered lowering the string tension on your RDS?
The Fischer racquet has enough mass, but is a little underpowered (the midsize version, at least) , and for me it worked best when I strung in the low 50s.
Perhaps if you lowered the tension by about 5 lbs on your RDS racquets before buying a new set, you might save some money.
Then again, maybe you are hell-bent on buying the Fischer racquet.
It is a great racquet.