Slapdash is another of those characters that wasn't used in fiction much. He was introduced in the comics, was in a few stories, and then disappeared due to the fact that no one could be bothered writing him at that point. The G1 cartoon had ended too, meaning that really there was only one choice; go to Japan.
Road King, as he was known in Japan, was a completely different character to Slapdash. There, he was a British racing driver, the 'British Wolf', with an eye for the ladies and a celebrity attitude. He certainly wasn't Slapdash, forgetting to take along his partner Lube (yes, yes, I know) which meant that he couldn't transform. If I'm being honest, Road King's a bit cooler than Slapdash. I'd rather he be Road King. I like Masterforce. A lot.
Slapdash suffers from what a lot of later-era Transformers suffer from - fiction drought. Because the cartoon had finished, and the comic was concentrating on a story arc rather than selling toys too much (toys were sold through the comic stories - but Furman was taking over by this point and the Matrix Quest was king, effectively), so some of the later era toys maybe didn't get the pushes that earlier toys did. Which is why I love the Japanese versions of these characters so much - they give these toys a purpose, a story. And it's a good story, too. If you haven't ever checked Masterforce out - do so, and do yourself a massive favour.