I don't think either are easy to find, if you have one awesome! if you can get the other have both! My vote is for Alien Star as I like that era/style better than the slightly later Robo-War although I wouldn't mind have one of those too.

I’ve played both but I prefer Alien Star. That said I only played Robo War at a show maybe ten times, I played Alien Star 200 times at my local arcade. I bought an Alien Star for my collection. If I could find a Robo war I’d probably buy it also

Both are great games but I prefer Alien Star out of the two. Robo War has more shots, drop targets and better sound but Alien Star has the best spinner rules in all of pinball. It's also the best game to Shatz the inlanes on as it's necessary for setting up massive 50k spinner shots! Whenever you get the ball in multiball it's a rush to play and try to cash in even though it's extremely difficult to do so. Robo War reminds me a bit of Sinbad as far as the drop targets bank rules go.

If there was one sitting next to the other, I would make a beeline for robo-war.

Robo-War is my fav Gottlieb game (even above TX Sector), so my vote DEF goes to RW

If you ever want to sell that robo war please LMK! Ive been looking well over a year now.

Yes, it was designed to be an updated version of Sinbad.
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