Search registered userprofiles

Hi there,

im planning on building a profile-website where users can register to my website and create their own profile. Companies can then login to the website and search these profiles for suitable persons to hire.
That's it in a nutshell.

Now i'm searching for a way for it to be possible to let users with a certain usergroup search other users within a certain usergroup. Is that even possible within MODx?

Or should i go for a seperate db which I then link via userID to get additional information about the found user? So i keep the additional info outside MODx and search through it with the help of snippets.

Which would you prefer?