I believe I can claim to be a connoisseur of most things chilli, and I have tasted every chilli sauce I can lay my hands on (certainly over 100). Tropical Sun is at the hot end and is similar to the widely available Encona. Both partner hot kippers very well. The best EVER, should you see it, is a Scotch Bonnet sauce from a company - or rather one woman working from home - called Pickle and Spice Co, in Harrow, NW London. It's a simple sauce, little more than scotch bonnets mashed up in vinegar (which type though?) with lemon juice, but it has a magical hot hot hot taste and pronounced effects on intestinal motility!
If you want a painful experience, go for the purified capsaicin sauces, with colourful names such as Dave's Insanity Sauce, but beware, they can cause severe pain, leaving you gasping and really really "I wish I hadn't done that".
The hottest chilli in the world is the Dorset Naga, grown near Dorchester. I have 3 boxes in the freezer, and just one of these things chopped into a vindaloo gives it an extra sparkle.
I just counted, my stocks are low but even so I have currently 12 different brands of chilli sauce - have you heard of brands such as African Farms (not too hot, but very tasty), Linghams (very sweet), Baron (look out for the Blazing Hot one), and Kanda (available in some ASDAs and very hot).
Chilli, arguably one of life's greatest pleasures.