Previous employee of Dating lab here, some info you guys might like: All in-house dev done on linux, content and profile vetting is taken very seriously, there is a dedicated team making sure no one get's scammed and profiles are real people. There is checks and balances to prevent on-line stalking also.
The two-way match algorithm is also pretty beefy and rather impressive. A few of my friends are married to partners they met on one of the datinglab network sites, a few employees also. These guys have been in the business a while, they know what they are doing.