Welcome to the forums!
When I enrolled in PWB v3 last year, I paid for 60 days lab access and even went back to purchase additional days after that. Around that time I was giving lab more than 3 hours a day, but out of the paid days, I may of missed a couple.
I'm with WCNA, you may want to spend as little money as possible, but if your going to be giving it 3 hours a day, You may want to consider the 60 or 90 days. The labs are huge! Over 50 machines spread out across 4 subnets to hack away at! Mix that in with the time it takes to do the exercises, extra-mile exercises, documentation, reading over the pdf, going over the 8 + hours of course videos, working on the official report...your going to have your hands full big-time.
If I recall correctly, I think in PWB v2 or OffSec 101 they had posted that the course content will be at least 40 hours long. It's expanded out a lot since then - I remember when I was in the course, PWB almost becoming a lifestyle believe it or not. The course was full of some pain, but remained fun and addicting. I was like yourself thinking, "I'm going to put 5 hours in on labs today", but in reality I'd spend a lot more time in there then I had planned; but it all worked out for the greater good!
Anyway, good luck on making the right decision, there's a few of us that have our OSCP certs on this board, hopefully you'll hear their input before you officially pay for the course.
eCPPT (Silver/Gold), GSEC, GCIH, OSCP, OSWP