Drools 4.0.7 Or 5.0.X ?

Hi Mike,

   We want to implement drools as our rule engine , planning to use drools 4.0.7 since i am thinking drools 5.0 has bugs and fixes is going on .Our project is going into production after 1 year so please let me know is it good idea to implement 4.0.7 or 5.0.X ?

Our application is standalone application not using BRMS this is one reason to select 4.0.7 but our application huge volume of facts performance is main criteria,planning to use RuleFlow as well.

Thanks & Regards
Surya.