Yes, I tried it.
Yes, I liked it.
It didn’t change my life or anything, and I’ll probably get some more of it at some point, but I don’t consider this stuff essential. I don’t much know how to describe the flavor, but there’s an odd strange fruity sweetness that isn’t there in “regular” Coke. Where the Coca Cola people got the idea that this is what space tastes like, I will never know. To me it’s just a neat new flavor for cola.
I had the Zero Sugar version, because filling myself with sugar via soda doesn’t seem wise these days, and besides, soda companies are really doing impressive things with the “zero sugar” thing nowadays anyway. The days of “diet” sodas having that unpleasantly weird metallic taste (which I’ll admit I loved in Diet Pepsi) seem to be over, as the Zero Sugar entries get more and more impressive. Sunkist Zero Sugar orange soda? That stuff is a gamechanger.
In the case of Space Coke (I only call it Space Coke, sorry, Coke, I know that “Starlight” is a pretty and poetic name, but it’s Space Coke), I suspect that I would find the full-sugar version ridiculously sweet. This also possibly tamps down the “space” flavor, which I’ve heard described as “cotton candy in a cola can”, which doesn’t sound appetizing, does it? But I liked this stuff.
I would suggest taking my recommendation with a grain of salt, though. I am, after all, one of approximately nineteen people who in 2004 actually liked Holiday Spice Pepsi.