Doing OVT at the moment too. I posted a question about a few days before you posted yours and it was very similar, you can search for the post, the title is:
OVT For Life.
The answer is: yes, do it for 8 weeks, two blocks of 4 and then take 1-2 weeks back off (so lighter loads) and then i'd swicth program, maybe to one of Chad Waterbury's workouts for 1 month and then go back. It'll make it less boring and avoid your body adapting to the program.