In the end, you know the most about the particulars of your situation, so if you feel you’ve done the research and talked to your customers and they all fall into this one value level, I say go with the one tier.
While googling around a bit I came across this consultancy that does pricing for SaaS businesses, and they have some very harsh things to say about using a single price point.
On the other hand, Ian and the team working on Snappy have actual experience with it, and it’s working for them. So we know it can work in the real world. @ian: honest question, have you had any regrets about going with one price point? From what I’ve heard previously, it sounds like you’re really happy with that decision.
In regards to your original question @Lewis, the Price Intelligently ebook says that only 5% of the 270 SaaS’s they surveyed use a single price point, so finding additional examples might be a little tricky. But I suppose you know that and that’s why you posted here. Maybe you could email the Price Intelligently people and ask them for the list of single price SaaS’s? The only email I saw on their site is firstname.lastname@example.org. They’re on Twitter @priceintel.