I've had 5 of the 7 superpins in my collection - they are all fun and unique with great theme intrigration - you can't go wrong with any of them. They were all built during the height of pinball in the 90's and you can see the great creativity that went into the design - being able to build a game without much of a budget constraint I'm sure also helped.

My favorites are:
IJ - great use of the theme in the modes, art, music. Multiball is easy to start but hard to get those super jackpots and addictive to keep trying. Also, if my shots are on game has nice flow hitting the ramps
DM - awesome flow, great music, again good use of the theme and the 4 main multiballs are fantastic
STTNG - great flow, love the beta ramp to loop to delta ramp - feels so good to hit, borg multiball is good and the modes are fun too especially search the galaxy. And another great game for theme intregration with the cast doing custom voice calls

The other 2 I had:
JD - great heavy metal music, dark humor, excellent art on the pf and bg, game has some cool shots with the upper flippers and the ball lock is very cool. But the game play never really drew me in for some reason. I thought I would love the game, but there is some fun or addictive factor missing imho
RS - I love hitting the ramps to bulid the multiplyers and finish with the blast zone shot but again the game never drew me in. I think the game is lacking in that you always stary with the same 2 modes and the upper flipper the only shot is red. There should have been a ramp or loop to hit with that flipper. I'd buy both again in a collection of 20+ games but in my small line up they didn't work for me

Although I never owned one GNR is a great game that I have played many times. I would love to own one some day