I have both a 190 SL and 250 SL. The 250 SL is an easier drive and more technologically sophisticated car. The 190 SL is more vintage, better looking and classier in most people's eyes.
If he thinks a good 111 3.5 coupe is too expensive, he won't find a decent 190 SL for the same price. A good, well sorted, 190 SL is $75-100K or more. You can find nice, drivable 113s for $30-40k with great ones for $60-70k. So there is a big price difference. Tell him to get the 113 and be on the hunt for a 190 SL. Maybe he'll get lucky.