HKR Womens Trainers with Arch Support Non Slip Work Shoes Comfortable Slip on Shoes Walking

I sit between a uk 5 and a 6, with narrow feet. What size would be best?

I wear a 4 in trainers but a 3 in dress shoes. Should I get a 4 or 3.

are they comfy enough to go for an all day shopping trip?

I saw the review, someone said that these shoes caused blisters! But i'm not sure, because more people said that they are comforable. Can anyone tell