Originally Posted by
Saekee
yes there is great synergy! I agree with you here. I guess the main loss is that one cannot take also the full assassin line to the level 18 core, which would give vorpals on sneak attacks (as well as further sneak attack dice beyond that which the DS replaces--3d6. Assassin tree gives 4d6, although going 6 levels of ranger does not exclude them). That rogue 18 vorpal also includes ranged attacks. If using a Radiance repeater, those vorpals will proc for a lot of damage. I guess that would be the deciding factor for me.
There are also other bonuses to staying pure rogue, such as the special feats line (mostly for improved skills after Improved evasion) which help UMD etc.