What's the problem, exactly? It's a rare (and usually unprofitable) niche that has no competition, and if you don't have competition when you start, you'll likely run into it later.

You already say that your solution will be a better fit for your customers; if that's the case, it should be simple for you to draw up a mental list of differentiators that can constitute your "unique value proposition", and pull these out when a prospect asks why they should choose you. (Hint: price is not always a great differentiator.)

If you run into prospects who are already using the competing solution, ask them how it's working out for them, and what kind of things they wish it did differently.