Given $1k spare cash to spend on insurance or investing? Which would you spend on? What product would you buy? And why?

Imho,

Your insurance should cover all the basics required.

Minimally, Health insurance is the most important (as hospital bills are largely the one that could cause catastrophic risk to the finances of the personal finance).

The rest really depends on your needs. You could diversify to a few investment depending on your risk appetite.

Not limited but including

Stocks picking (high risk)

Robo-advisors / ETF dollar cost averaging (medium risk due to the etf)

Or just stash up enough in a highest interest savings account to build up both your capital and investment knowledge.

$1k a month? Insurance. The product you buy would depend on your needs/wants.

I would accumulate the money leftover to invest.