Excuse me for the late comment but I was unavailable. As here are plus 8 votes for the suggested feature, I am sure it will be added to the top of gidgreens list for the next release. Meanwhile You have numerous techniques to avoid spam on a growing site.
1) You can block IP / users
2) You can use integrated recaptcha to avoid automatted spam subissions
3) You can set access to registered users only with or without confirmed email adress.
At the beginning using this script, I had some spam, but i blocked some IPs and added recaptcha and the problem was gone. Works fine for me on several sites.
Regarding other scripts I can only tell You, that in MY opinion, there is no other elegant solution based on php and mysql and Your OWN database. Even the paid scripts didn´t work for me.
The author of this script here, gidgreen, takes user input very serious and has added suggested features in an excellent way, so that very most users are satisfied.