Williams built MM's and all of thier products on a mass produced scale and quality control was likely reduced to making sure everything performed well mechanically so they could ship out to operators to put on location. There was no where near the home market hobbyist we have today to critique the details in the looks dept, a blemish on a playfield here or there did not matter much when your trying to make money with the machine. Now with a remake, 70% of these machines are being sold to the home user whom are a far more strict to critique the details on looks as well. The repro MM's aren't being made by some Podunk, fly by night operation, they will make sure the product meets the demand of the pinball hobbyists and the operators as well. If anything the repro will be the better quality unit, making the improvements on the new game where the original lacked.
Comparing a muscle era car to todays counterpart isnt going to fly here either, 40 years to compare a vehicle to the same model being made today is hardly the same thing to making a comparison to something that's made in the late 90's to the same product being made today, 15 years.
Ive also noticed a few of the hardcore Williams MM guys are bent on saying their machine will still hold its value the way it was before the announcement and always try to berate the conversation of the new machines stating the new machines will be a joke compared to the Williams. They either refuse to accept that their machine is now worth roughly 40% less then it was a few days ago or they are just in denial about it.
Anyone that actually believes an original MM will be superior over a reproduction needs to have their head checked.