#1
It is my understanding that the neck of a S470DXQM Ibanez is a 400mm radius, while the ZR2 trem is actually designed for a neck with a 430mm radius. Is this true, and if so, just how much will it affect a newbie?
#2
Not an issue at all. When you're talking 7.25" radii like vintage or AVRI Fenders, or possibly 9.5" on the modern ones, having a flatter bridge like a 12" can make a difference in terms of action. 7.25" looks like this:


400mm is about 16", which is a tad flatter than this:


And 430mm is about 17", which is even flatter. Obviously the larger the number, the smaller the difference each additional inch makes. I would argue that past about Gibson's 12" you're not going to get a discernable difference between radii, possibly 14" might be able to achieve slightly lower action while remaining bendable, but the difference between 16" and 17" is next to nothing, and certainly nothing to worry about. Schaller's 14" hardware regularly goes on 12" fretboard Gibsons without issues (for that matter, even plenty of Jazzmaster/Jaguar users, usually with the modern 9.5" radius, swear by 12" Gibson bridges; J Mascis uses them on 7.25" Jazzmasters, but his action is ludicrous so I'm not sure he counts. I digress...)

TL;DR it's not an issue at all, even if you want ultra-low shredder action.
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#3
The adjustments in the bridges (saddle heights, etc.) themselves will usually allow a bridge to adjust to other radii, so it's not much of an issue for most.
#4
Quote by dspellman
The adjustments in the bridges (saddle heights, etc.) themselves will usually allow a bridge to adjust to other radii, so it's not much of an issue for most.

Don't think ZR trems have adjustable saddles heights, but again I can't see such a small difference on what's already such a flat fretboard having much impact.
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