I can either buy a Focus ST cash or finance a Focus RS (just 12 instalments, nothing crazy)...

You didnt even read the recall
Typical ford fag ignorance

buy a 'stang GT lmoa

not a flashed up fwd econobox or an unreliable meme machine

What appeals to you in either of these cars?
Im genuinely asking.

I own a Focus SE and love it, I wish it had more power.

Youre going to lose about the same money on both so yes go with the rs

Get the RS. Fwd a shit. Drift mode, torque vectoring, higher output engine. It's a good investment.

Well, the ST is a huge pile of shit, and as long as you don't put the RS on the track and keep it stock, the RS is a way better choice.
Though I don't recommend either.

Buy a BRZ instead

Think about it. Everyone is going to be wetting thier pants in a few years when they eventually come off the market. They will end up like what the quattros and lancias are today