Here's a shot of a posable tentacle prop that I made about a 18 months ago. The model had 100 segments and was posed using a PoserPython script I wrote. As you can see, more segments will definitely give you a better curve. The script was written so that you could use any long cylinder shape not just this tentacle. I tried re-boning the Poser rattlesnake to increase the segment number and it work quite well with the script.