I sold my Schuran and went with a Geo. I am very happy with the Geo I bought. The Schuran, nonetheless, is a great reactor as well but if you ever break it or need a part for it, you'll be waiting 3 months and spend a 100.00+ on the part. I know it happened to me and one of the reasons why I sold the Schuran. The Geo is built just as well as the Schuran and much easier to maintain. On the Schuran you have to drain the entire reactor and remove the center body to change or refill the media. On the Geo the top twists off and you just pour in new media. Both handle the large style of media very well. Both have the Eheim pumps. The Geo does come with everything you need including a pH probe holder, check valves and all tubing to hook up. On the Schuran you have to buy that extra which is not expensive.
The Schuran I had to use a perisialitic pump to feed it or else it lost accuracy over time. Others have had better results feeding the Schuran with different methods. On my new Geo I am using a maxi-jet 1200 and it works perfectly and has stayed dialed in very well.
If I knew what I knew now back when I first bought my Schuran I would've went with a Geo. You can't really go wrong with either.
Another positive is the Geo is cheaper and it holds 8+ lbs of media and you can get parts cheaply and quickly.
I hope that helps.