Lycosaurus and ContiRex may be thought of as old and outdated, but I have to admit - I do like to fly them.
They do what I tell them to do and when I tell them, they are real easy to run and maintain by anybody with common sense, I am able to understand how and why they function, even guess quite quickly when they don't. The carb will give me direct feedback on environmental conditions, where already the injected engine is mysterious as my girlfriend.
The one I fly frequently now, already turned well over 50 years old and is still going strong on 3rd overhaul with no end in sight. I don't see a real progress in piston engine development either. I have to admit, I neither trust the car derived Fadec piston engines, nor things like Jabiru (which I would not call blessed with reputation anyways).
Maybe I have to fly too much turbine and jet, but I would like to see the old basic flying available for a long time. Call it sentimental, I call it joy of flying.