Maybe the higher prices are due to them trying to maintain a good profit-margin so they can make a bit of money to cover their overheads.
Anyway, I just did a tweak of the RG350DXZ's Intonation and I really think I've got it in the ballpark now, the guitar does seem to have better tuning stability than my S420WK did, especially after using the trem bar, it does seem to return to pitch pretty well, I've got the Zero Point System engaged, overall I'm pretty happy with the guitar to the point where I'm fine with it being my official main guitar, I feel like I can rely on the guitar in a gigging situation, so, this White Ibanez RG350DXZ is now officially my main guitar.
Feeling very relieved that I now have a guitar that does stay in tune, now I can get on with learning how to play it well, and how to play some songs...lol.