I think there's a tendency to discount the work of a good sales team in the tech industry.
If you are serious about growing a business, you need to be as serious about bringing on a great salesperson as you are about the engineering and product side of the equation. It is very unlikely that you will find this person by offering only commission. You need to build in a big upside to their compensation, of course, but also offer at least a small portion of the total on-target salary as base. If you don't, you'll get an influx of people, sure, but no one particularly good, and it will cost you more in the long run to keep recruiting and training (however superficially) these people. Best to focus on hiring a truly good salesperson who can partner with you to scale the business beyond what your abilities would allow you to do alone.
So the question becomes, How do I find a good partner for this? A few good interview methods I've employed and encountered are:
1) Have them give you a mock pitch for your product, and then have them retool the pitch incorporating your feedback in a week's time or so;
2) Have them speak to someone you trust within your network who has sold and been held to quotas before;
3) Ask concrete questions about how they envision their process helping your outfit in growing sales numbers - things like how they'd prospect, what their sales cycles would look like, etc;
4) Tell them how you are currently selling the product, and ask them to pick out a couple of places where they see an obvious potential for improvement.
Unless you and your team have the sales cycle tuned precisely, it is unlikely that an army of commission-only salespeople would help you move the ticker up in any meaningful or sustainable fashion. Again, sales is just as important as the product itself, so don't shoot yourself in the foot by treating this function of your business as a mere afterthought.