Others may answer with more competence. My two cents are, that on one hand Mogs have a good status regarding low depreciation, also new cars. On the other hand, because they are being built over all this decades with minor changes, the old ones have to compete with the newer ones. Therefore a 30 Y old Mog never can reach the value of another attractive brand/model, which numbers are limited to their decade of production.
To keep on the Porsche madness of this thread, I have purchased some Porsches. All but one are for sale. NOTE! I don't want to sale anything here!!. This is a private site. What I want to tell is, one will stay with me. Here are two close candidates.
A very rust free 1973 CIS T Targa in my most favorite color Tangerine, matching numbers original color code (if also resprayed), I have registrated her since three months and testdrive her. A beauty in my eyes, very nice cruiser, but relatively expensive and a bit slow...not really slow but no thrills. So she perhaps could leave.
The other candidate is this 1985 3.4 Carrera. Half an outlaw, reasonable purchased and a top driver. A third of the price of the Tangerine.
The picture is from California before I bought her.
The description is unique (if you like to click) Jay Jarvis (some could know him) personally made her five years ago. Unfortunatelly he past away two years ago.
Both lovely cars, I suppose I would have liked to see a few more photos of the earlier tangerine car as for me it looks quite period and I like originality in classic cars. The later car is fantastic also and has obviously has some sensible modifications. I would be very torn between the two cars but on the basis of the photos I would probably hold onto the earlier car.
John
1989 911 Porsche Carrera Land Rover Series Defender 90 SW
The black car turned 30Y this August, so she is just before to be registered as classic car with low tax. After driving I may see better which one I should keep. The black Carrera with her serious made mods will be a fast car with Mahle race pistons etc. and ca. 280 natural aspirated horses. The Tangerine is a nice lady, the Black is a cool driver. I will see...
You know it makes sense! 
