I've discovered a nice combination, however, that can be both hotter and taste better. Scotch Bonnet peppers[1] are widely used in the Caribbean Islands, and are almost, but not quite, as hot as as Habaneros, but they taste MUCH better. OTOH, Naga Jolokia "Ghost Pepper" peppers[2] are much hotter than Habaneros, and taste, well... not any worse than Habaneros, at worst. So, if you want to jazz something up to nuclear hot levels and keep it tasting good, load it down with Scotch Bonnet and then add just a few drips of Naga Jolokia pepper sauce.
This has become my "go to" combination for making really hot tex-mex type dishes, curries, etc. Yumm....
FWIW, my favorite brand for both (at least partly because it's available retail locally) is the "Tropical Pepper Co. brand)[3][4].
[1]: http://en.wikipedia.org/wiki/Scotch_bonnet_%28pepper%29
[2]: http://en.wikipedia.org/wiki/Naga_Bhut_Jolokia