Like @CarlSpackler said Ping has the color chart system. You said you have black dots? You can take your own measurements at home and see if if the length and lie are correct for you. It's an inexpensive way to do it. Length and lie are pretty cheap fixes to make.
To answer your question simply, no I don't think you're missing out with old irons. My first set of irons (which I still have as backups) were from the 1990's. The only reason I upgraded was because the lofts on the modern irons are much stronger, and it allowed me to get rid of the 4-iron.
Thanks for the replies.
Generally my miss is right with the long irons, left with the short irons, and overall, I'll hit a bit heavy if I don't strike the ball clean.
So it wasn't just me thinking the pictures of these newer irons made them look giant. Sounds like there isn't anything revolutionary that I'm missing out on, maybe I'll just casually try to hit a few different ones and see if I notice any difference.