Personally, I like their "Vusa" (the hottest) rather more than their other "hot" ones but I would agree that, in general, I prefer the taste of their mild items. They overrate everything a little, in my opinion, but their black label "extra extra" is at least hot by restaurant standards and the Vusa isn't too much milder than a typical Ghost sauce. Definitely worthy of my 4.5/10 heat, from what I remember.
In the end, though, perhaps peri peri isn't my thing but I find them decidely ok, both in their sauce range and in the actual food that they serve. Not bad, per se, just nothing great or special.