It is definitely not better than the RG series. I own an RG370DX myself and have played both a GRX40 and a GRX70 and they are far inferior as far as construction and tonal quality go.
But since you are a beginner, you probably won't find much of a difference. As you improve with your guitar playing you will begin to notice the difference between your guitar and other better quality guitars. Anyway hope you enjoy your new guitar and practice well.
Since the creation of the Internet, the Earth's rotation has been fueled, primarily, by the collective spinning of English teachers in their graves. (QDB #754533)