I happen to own both an '86 300E with a 5-speed manual and an '87 190E 16V also with 5-speed. All the magazine reviews I've read about these cars suggests that acceleration is similar. This may be true, however, the feel and character of the two cars is completely different. Where the 16V is quick and agile, the 300E is smooth and comfortable. The 300E chassis is more refined and offers more room. Both are very satisfying cars to drive in their own way. I suggest you drive the 16V (preferably through your regular commute) and see if you like it.
The 16V requires a little more maintenance with solid valve lifters needing inspection/adjusting every 15K miles. The self-levelling rear suspension needs regular fluid changes and the nitrogen cells will probably need replacing every 100K miles or so. Other than that, maintenance on the two cars are similar. Both share common weak spots typical of many MB models from their era: acc (a/c) failure, cruise control maladies, window switch gear, radiator inlet necks, and antenna masts.
'86 300E (5-speed)
'87 190E 2.3-16 (5-speed)