My experience is that sometime "draft" option produces a better result.
Some "strange" lines don't appear in "draft" mode.
For example when you draw some very thin cladding (5mm or less), in "best" mode you see what is behid the cladding, in "draft" mode you don't see that ... What does it depend on? On the graphic card? On some registry key settings?
AC27 latest hotfix
Win 10 Pro 64bit
Double XEON 14 CORES (tot 28 physical cores)
32GB RAM - SSD 256GB - Nvidia Quadro K620
Display DELL 25'' 2560x1440
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