I have one serious concern about the value of any "modern" cars collectibility. My problem with modern cars is the special computer systems that are used. They are usually specific to each model and year of the vehicle. What happens when those computers fail and none are available? These are not something a shadetree mechanic can repair. Does this concern anyone else? Collector cars up to now have been prior to 1980 models that weren't computerized. Think about repairing them by putting new points, condenser and coil. Block hardware should always be available (pistons, bearings, rings, etc). But what happens when a computer goes south? Will this affect the collectibility or not?
Mercedes will re-manufacture any part required for any car they have built!! I know myself, trying to get hold of obsolete electronic components or their modern equivalents can be a nightmare - especially older CMOS devices. I wonder how they'll get around that without a total re-design.
LOL, by then they'll have a computer about the size of a watch, the adapter cable will be bigger than the computer. It will plug in and be adaptive (self sensing) to the car that you have and give the car what it needs electronically. The engineer will say that he can't believe how they use to do it in the "Old" days. It must have been like the stone age!
There were over 300,00 R170s built, along with 80,000 Crossfires, so parts should be around for quite a while and the numbers are enough to justify some alternative sources. Unlike many "collector" cars Mercedes is still in business and likely will be for a long time. I have been a long time owner of an MGB. You can built a complete car out of newly sourced parts if you have the time and money. As far as the electronics go, they can almost always be worked around, rebuilt, or replaced with newly manufactured copies. It is going to be a matter of time and money. There are still plenty of people using reworked MGs from the 60's as daily drivers. besides the R170 is too beautiful to let die (or mod, but that is just me).