The O200 is a very heavy engine, it burns more fuel, is NOT designed to run on 100LL or Mogas. It has a very bad reputation for falling out of the air due to carb ice, it cracks up due to shock cooling and it uses notoriously unreliable magnetos which is technology which was ok for a 1920’s tractor but has no place in a modern engine. Remember the mags will need maintenance every 500 hours.
The Rotax is a lot lighter; burns much less fuel, are almost immune from carb ice and do not suffer from shock cooling at all. The duel solid state ignition system is maintenance free, is 5% of the weight of magnetos and has a MTBF which is vastly better than a magneto. Because the Rotax is the dominant engine in terms of numbers there is a superb array of fixt pitch, ground adjustable and VP/CS props available at a fraction of the cost of the O200 equivalent. The generator on the engine is built in and does not require an elastic band to drive it.
Having flown behind both engines I find it hard to see why anyone would choose the O200. In the PFA fleet the most reliable engine is the Rotax 912 range.
Rod1