I purchased Brooks Brother's Chinos between 2012 and 2019. They closed their York designer outlet store. They feel the best to me, they have changed the design periodically. There is one style I prefer. To continue buying them I would need to travel to their central London stores or order online from the US. However even sales prices do not come near the discount offered from the former outlet store. The outlet cost was £55.00 but often had 30% discounts. In the store they are £150.00 and made in Malaysia. I now order online from Lands' End, they are around £40.00 to £50.00, but there is a permanent 40% off sale on. I have bought many at between £14.00 to £18.00. I would like to buy made in UK Chinos, there are a few sites that exist. I have bought made in UK Chinos from Cordings, but the fabric is very thick. If M&S restocked their Supima Chinos, I would check them out. When I did became aware they existed they had sold out. The York designer centre has a Ralph Lauren Polo store, I have bought Chinos for my brother before, but they generally not available in my size. I intend to check them out in future.
I did buy a pair online from Banana Republic, they are absolute garbage. I also buy 100% cotton, I have now stopped my boycott of non iron products as I wouldn't be able to buy anything from Lands' End or Brooks Brother's.
TM Lewin has Chino fabric from a few prestigious Italian mills, but they are for 32 inch waist crowd or with stretch. I may look at a few Italian and German brands, but the Land's End Chinos are excellent value.