How about both, personally it depends on my mood. I love exploring new water and finding new holes and some new fish. I also hate blowing a whole day not finding fish or not fishing. It's always a gamble but is it worth rolling the dice? I say most definitely but you want to have some of the odds in your favor. Some things to consider, how long will it be until you get to fish again, is it a place you plan on visiting again, and conditions. I don't care how good a fishery is if weather is bad or conditions are terrible it can make fishing new water extremely difficult. How long will it be until you can fish again? Because if it's going to be awhile I would rather bet on the sure thing. None of these things really matter if it's close to water you know or close to your house but it can be disappointing driving 3 plus hours to find out you don't like the water or it's not fishable right now. If it's close you can always swing by your honey hole on the way home.
This summer I experienced both ends of the spectrum found some really good spots I'll hit again and found a few spots I don't care if I ever fish again. I think the biggest reason to roll the dice is might just find your next old faithful. You don't know what's out there until you explore it for yourself and winter is always a good time to start planning you attack for the spring.