Opinions of Bosch Platinum +4

[96C280]

I've read posts on Bosch Platinum +4's and the opinions are mixed.

1. Is the engine in my 96 c280 considered an older engine that should avoid the Platinums? What is the differentiaition between the "older" engines and "newer" engines....engine management system, valves per cylinder, etc?

2. What are the original plugs on my car?

3. I'm interested in Plat +4 because I do a lot of city driving and would like to avoid carbon buildup as much as possible and would like improved throttle response in stop and go traffic.

4. Has anyone actually returned Plat +4 to Bosch because they were dissatisfied. Can you return it to the retailer for a refund?