Micro niche or general review site?

Trying to decide whether to go for a micro niche site for my next site or a more general best reviews type site. What reasons are there for not doing the second one as this would allow a muge larger ranger of products and hopefully more revenue.

I would expect it to be a bit harder to rank though when the site is not as specific.

Thoughts?

One of my clients has 15 different online stores with some overlapping products. This client merged them into one authority domain which helped our paid advertising metrics a lot but killed SEO because in general Google limits a site to 2 results in the SERPs... So we went from dominating most of page one to having 2 results on page one. One big website, while a boon in media sales, was a loss in organic traffic for this large e-commerce website.

If you are site flipping then one authority Site has better stats because they are combined. If you are trying to be a retailer then multiple stores (that are tuned differently) gives you better reach into your market.

So it depends what you are after.