I do both but for me crochet gets quicker results. However, I am biased because I have invested a lot of time in crochet projects and not as much in my knitting.
Loom knitting is what I ended up doing after failing at crochet and knitting :)
For dishcloths, I'd suggest crochet because the end product is usually thicker than knitting for the same-sized yarn. There's lots of patterns available online or in craft stores, like this.
Here's an example of knitted dishcloths.
For a small project, you can go either way. Crochet is faster, while knitting only has two basic stitches, making it easier to learn. I don't think either are particularly difficult.
I have tried to crochet and failed, but I have been knitting for about 30 years.
I crochet. Have tried knitting and it is hard I think. With crocheting you can take on a plane because it is not sharp like knitting needles. I have been told