I'll do some processing of my 10 album test set tonight and post the results. For my 53 sample set and a slightly modified set of quality presets (-4=-3.5; -5=-4; -6=-4.5; -7=-5, but all slightly changed) which may feature in beta v0.7.9:
Preset [Equiv. Settings] Total Size Bitrate [Delta.BR] 10 Album Test Set
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FLAC [---------------] 72,652,785 bytes, 781.6kbps [--------] 3.35GB, 854kbps (-------)
-1 [-nts -4 -snr 25] 52,138,258 bytes, 560.9kbps [--------] 1.94GB, 496kbps (-65kbps)
-2 [-nts -2 -snr 23] 48,177,581 bytes, 518.3kbps [42.6kbps] 1.78GB, 453kbps (-65kbps)
-3 [-nts 0 -snr 21] 42,976,155 bytes, 462.3kbps [56.0kbps] 1.58GB, 403kbps (-59kbps)
-4 [-nts 3 -snr 20] 40,324,698 bytes, 433.8kbps [28.5kbps] 1.47GB, 375kbps (-59kbps)
-5 [-nts 6 -snr 19] 37,934,855 bytes, 408.1kbps [25.7kbps] 1.38GB, 352kbps (-56kbps)
-6 [-nts 9 -snr 18] 35,826,396 bytes, 385.4kbps [22.7kbps] 1.31GB, 333kbps (-52kbps)
-7 [-nts 12 -snr 17] 33,950,736 bytes, 365.2kbps [20.2kbps] 1.25GB, 318kbps (-47kbps)