really this is going to come down to the build quality of the person who put it together. There are quality MK1/2 that the builder spent the time to build it right so it is holding up well. There are MK4 that have horrible build quality and would be death traps. Whether MK1/2/3/4 you need to see it in person and if you have not built one there are people in this group that can help assess it for you. Quality of wiring, fit and finish, fluid leaks etc. I would not discount a quality build no matter the mark number. Just my 2 cents.