The penalty has been more or less hamstrung by the GOP, so if that's your only consideration, then, yes, you're better off not paying for health insurance.
Additionally: you can (you shouldn't have to, but you can) shop around for cheaper medical imaging. Imaging in particular has wildly varying prices, and if you stay on the "happy path" your PCP and hospital puts you on, you're going to pay the higher end of the range of prices.
You are not, as a general matter of life advice, better off going without health insurance. Rather, find the least expensive HSA-qualified HDHP, fund the HSA with the savings, and pay for routine care (effectively) out-of-pocket. The point of insurance isn't to make your annual checkup cheaper, but rather to avoid going bankrupt if you get hit by a car or your appendix bursts.
From the way you write, your appendix presumably hasn't burst yet. That's great! Neither has mine! My house has also not caught fire† and I have not managed to crash my car into a fully occupied city bus. But I am insured against both of those things, too.
† since we bought it, i mean