For me personally, I've reviewed a range of Sass solutions for our business and pretty much every time I'm happy if there's a demo video of some common use cases your software solves.

Doesn't necessarily need to be a long winded mega demo - a couple of minutes is plenty to give me a feel for whether your software is initially a potential fit for my needs and if I'd like to follow up on that interest.

After that point I don't mind speaking to a sales person if necessary, it just feels that when the very first step is potentially a sales call (even if it's actually just one of your team offering a demo instead of hard selling) is offputting to me.