SuperSpeeds = good (American-made, date-coded, cheap as chips.)
Rockets = better (English-made, heavier and heftier than SuperSpeeds)
Aristocrats = best (English-made, heavier and heftier than Rockets)
An HD (= heavy duty) Rocket is basically an Aristocrat in terms of weight but are relatively common and cheap.
SuperSpeeds here: <!-- m --><a class="postlink" href="http://www.theshaveden.com/forum/showthread.php?t=9070" onclick="window.open(this.href);return false;">http://www.theshaveden.com/forum/showthread.php?t=9070</a><!-- m -->
Many Rockets look almost identical to SuperSpeeds; Rockets were almost the same razors but made in England - they do not have any date code but they do have a different (and immediately recognisable) "gap" between the handle and the TTO knob and pointed end-caps. In a nutshell: Rockets are a superior version to Superspeeds.
Mouth-watering Rocket info here: <!-- m --><a class="postlink" href="http://www.theshaveden.com/forum/showthread.php?t=9206" onclick="window.open(this.href);return false;">http://www.theshaveden.com/forum/showthread.php?t=9206</a><!-- m -->
English-made Aristocrats (and, yes, there's rubbish American ones too - just to confuse you!) are Rockets on steroids. Like Rockets they all say "Made In England", they all lack a date code, they all have pointed-end caps and they all have the Rocket "gap". But they are even bigger and better than Rockets (which, in turn, are bigger and better than the US-made SuperSpeeds)
This chart shows the difference between the numbered (English-made) Aristos such as the #66:
<!-- m --><a class="postlink" href="http://badgerandblade.com/vb/showthread.php?t=91556&highlight=aristocrat+guide" onclick="window.open(this.href);return false;">http://badgerandblade.com/vb/showthread ... crat+guide</a><!-- m -->
HTH
Ollie