Tbh, instead of recommending different things we should be asking the condition of your paintwork, age of the vehicle and how it's been maintained/washed?
My Leon is a 2014 with 48,000 miles and the paintwork wasn't in great condition due to improper wash techniques carried out by the previous owner and dealership.
It's really easy to buy a decent product and slap it on, however if your paintwork isn't perfect you won't get the best results and could be disappointed with the product.
That’s spot on!
Durability of the product will be compromised if it’s applied to a ‘dirty’ car. By dirty I don’t mean caked in dirt, but a car where there are embedded contaminants in the paintwork that should be removed by claying, the use of a fall out remover and a tar spot remover to ensure the paintwork is completely clean and feels slick before applying a wax or sealant of choice. Doing a full decontamination will prolong the durability of the wax or sealant - I’ve learned this from experience.
The results I get now are very different from what they were some years ago in the days when I belonged to the single bucket, sponge and wash leather brigade, and also used to apply wax to contaminated paintwork. Things are different now though; when I last waxed my car (October last year) it was after I’d carried out a full decontamination and machine polish, and eight months later, water still beads up on the car when it rains. And using a safe wash technique helps to keep the paintwork swirl free.
As for the OP’s original question - what’s the best polish? Everyone will have their own favourites and views on which products are best - be it a polish, wax or sealant - as the posts in this thread shows. I have no doubt there are better products than the ones I use, but for me the main considerations are good durability, ease of application and removal, high gloss and good value for money. If it ticks those boxes, then it’ll be on my shortlist as one to buy.