If you wanna compete with drug free athletes try PA. If you don't, GPC.
As an outsider looking in I can see Freako's point that GPC will struggle for public acceptance with its non drug testing.
Although Sticky has previously stated that GPC don't test because of the financial burden I can also see a reason why an organisation might give up on the whole circle jerk of drug testing when lots of users slip through the net, apparently.
Just a question, if GPC don't test, are there any substances which on competition day would enhance performance ie. Cocaine, Amphetamine etc. That would be a worry.