When is it better to target specific (English speaking) countries?

In my last thread I had asked how you would go about setting up a website to cater for traffic from different countries, but now I'd like to ask about when it's better to try and rank with location modifiers and how to treat the website.

What I mean is, a niche I'm looking at looks moderately challenging to rank for a keyword like "best PRODUCTNAME" - but if you search for "best PRODUCTNAME uk" then the search volume is obviously not as much, but the competition seems like 0.

So what I'm asking is what the best thing would be to do? Should I get a .co.uk domain and focus on the UK? Or get a .com domain and focus on the UK, or get a .com domain and write an article talking about the best in the UK and try to rank that subdomain/article? (Or any other options).

I assume that trying to come up with good content with a twist on location about a product that is the same all over the world could be damaging too?

I hope this makes sense and doesn't sound like it's just poured out my fingers (which is pretty much has).

Thanks!

Get co.uk domains to focus UK Rank & Traffic easily without any competitions

And Make Good Quality product contents to gain more visitors daily.

SearchEngineWays said:

Get co.uk domains to focus UK Rank & Traffic easily without any competitions

And Make Good Quality product contents to gain more visitors daily.

Click to expand...

Thanks - I suppose I could always start a .com in the future once I'm more competent at competing in higher competition niches.

To add to this: would it just be better buying a .com domain and using the modifier "UK" in my titles/headers instead of going all out with a uk domain name? Or what is the general consensus of whether .co.uk ranks better at google.co.uk rather than .com ?

Sorry for the bump, but any opinions on this?