Looking at the chart, you can see the difference is astounding. At lower levels the difference in items needed is not too significant; 6 vs. 8 at +3 does not seem like that much vindictus gold, in terms of +0 items.
But statistical probability isn't the only thing we can consider in this game. All materials involved cost money, and armor and weapon enchant stones are SIGNIFICANTLY cheaper than their enhance stone equivalent, at [beg], [int], and [adv].
As far as stone cost is concerned, enchanting is therefore the better bet, because at lower levels the enhance stones would usually cost more than the items themselves. Essentially, while low-level and dealing with lower-leveled weapons and armor, you are better off enchanting your items.
This’ll happen, and your weapon will get +1 to its grade. I think there's also a tiny, tiny chance that it'll get more than +1, like enchanting, although I can't personally recall this happening to me. Could someone confirm this for me?
If you're unlucky, this'll happen, and the item and stones will be reduced to nothing but a memory. Don't worry, though, it happens to the best of us, and you've just got to pick your feet up and try again, among other cliches.
However, when dealing with accessories and higher-leveled equipment, the item cost FAR outweighs the enhance stone cost.