This will depend on the site, branding, messaging, person's opinion, etc.
There are studies arguing for both, but you won't know the true answer for your site until you A/B test them.
My opinion: even numbers give a more premium / boutique feel, while decimal pricing gives a feeling of being on sale.
To get the best data, you'll want to try both.
On a basic level, with Shopify I like to test one variation for 24 hours, then the next variation for 24 hours, run it for a couple weeks (depending on traffic level), then compare the results of each. If you need help with A/B testing let me know.
I find that with the price of decimal, suppliers hit the right psychology customers like cheap prices but buy quality goods. This is also an effective and widely used way of selling in many countries