Hi mate, SOF is compared alot because of the artwork of the game. although they play n feel very differently, the artwork is very nice and those 2 x machines (BK2000 and SOF) also look great together. ALSO being same system 11 means they were built near each other time wise etc either.
People often like both games because they were alot modern looking for the year they were built. Both really good players.
Dr Dude is bright n colourful and a positive/fun machine. Again, a fun game. ALOT of the system 11 games were built when pinball was just about to boom and people had just started to add alot to these games and really push the envelope.
You cant go wrong collecting system 11 games thats for sure.