Technically, the low mass Grace 707(if your Grace arm is in fact, a 707) would not be a very good match for the 12cu compliance of the Dyna 10x5. It would put the mass/resonance figure outside the "optimal range".
However the Grace arms have good bearings, and can handle the stiffer compliance of this cartridge pretty well.
So, if you are not noticing any serious resonance faults in the audio band, perpetrated by the cartridge/arm matchup, you could get away with it.
There is a good chance that you are also losing some dynamics and low end, due to unwanted tonearm movement caused by the light arm and stiffer cartridge.
I think the Goldring 1042 was a much better match for your arm.
Until I looked it up awhile back, I also was under the incorrect impression that the 10x4 and 10x5 cartridges were higher in compliance than they actually are. The 12cu compliance is actually on the "stiff side" of the medium compliance range, and could be considered low-medium compliance.
However the Grace arms have good bearings, and can handle the stiffer compliance of this cartridge pretty well.
So, if you are not noticing any serious resonance faults in the audio band, perpetrated by the cartridge/arm matchup, you could get away with it.
There is a good chance that you are also losing some dynamics and low end, due to unwanted tonearm movement caused by the light arm and stiffer cartridge.
I think the Goldring 1042 was a much better match for your arm.
Until I looked it up awhile back, I also was under the incorrect impression that the 10x4 and 10x5 cartridges were higher in compliance than they actually are. The 12cu compliance is actually on the "stiff side" of the medium compliance range, and could be considered low-medium compliance.