The penetrators have a replaceable tip. The regular shureshot points don't. By all means get the ones with the replaceable tips.
Also, I recommend wrapping a bit of teflon tape on the threads of the penetrator tips. There's a little how-to article on our home page
http://www.illinoisbowfishers.com/ titled 'Teflon Fish Point Tip'.
Personally, I use Shure Shots, a couple different styles of Cajun points, standard Muzzy points, Innerlock grapple points and Pro-points and a couple others.
Just depends on what kind of fish I'm targeting.
The Muzzy, Cajun Piranha and Shure Shot are my 'all-around' points and I think they all work equally well.
For soft fish that arrows tend to pull out of (big buffs, grass carp) I like the points that have more barb... such as the Innerlocs or Cajun tournament tip. These are a pain to pull out of weeds and roots tho'. Muzzy has a new four pronged tip that I'll try this year. I have friends that swear by the Gene Davis and Cajun Lil stinger 4 barb fish points for soft fish. I'll have to try those this year too.
There are a lot of choices.