Yeah. There are plenty of variables that affect the effect of DRM toward a certain product too (sales region, type of software, market segment, platform distribution system, etc).

But what I know is if there is an easily obtainable copy online of your system, for free, then you will definitely lose some potential sales over that. Whether the 'free publication' you get out of that free, unauthorized, distribution makes up any positive gains in the future in anyway, no one will ever know. I'd say: many of the future distribution of the product will most likely be based on the free, unauthorized & uncontrolled copies out there anyway.