Dumb question: why is everyone so interested in getting the lowest possible scope rings?
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All else being equal, lower scope heights results in a stronger mount due to the reduce length of the mechanical lever arm (moment arm if you speak in engineering term). The shorter the arm, the lower the stress on the mount.
To me, it is just as important that they be correct height for proper eye alignment with good cheek weld, which makes stock ergonomics a factor. If/when those ergos result in higher scope heights, the strength issue can be resolved with different mount designs, but those solutions typically increase weight of the mounts.
For me, the biggest reason to mount low (or to mount higher in some cases) is to get the best cheek weld and eye alignment. Any other reasons are secondary (to me). The preferred height will vary according to stock design and facial/neck/shoulder/etc structure of the shooter. Using the same stock, pumpkin head needs a different height than pea head.
Lower will use less amount of scope adjustment for zeroing. In most cases it's not a biggie but it used to be a bigger issue with limited adjustments.
Related to that is better line of sight to trajectory. Again, in most cases not an issue. Doesn't change trajectory of bullet, just where it's crossing line of sight.
Canting seems more pronounced to the shooter the higher the mount. Again, not an issue if mounted correctly and leveled when shooting.
As mentioned, higher the mount, the more stress that can be put on it it. There are really good strong mounts now that should make this a non-issue.
For me, fit is it....anything else is not really in consideration for me.
