I'm of the mindset that conservative is better, but it depends on if you're trying to build a total or just smash PRs in one or two of the lifts. Conservative helps build the total, but too conservative makes it hard as you'lll have to make big jumps to PR. I know a lot of those on the internet (Brandon Lilly comes to mind) like these massive jumps, but anything more than 40ish lbs on squat seems tough.
You also say it's your last meet at 300+, so I guess who gives a shit if you miss, just gofor broke. That being said, it's all relative an your numbers are a lot bigger than mine. MY vote still goes to conservative though.