There aren't really many products one can buy in normal UK stores. If the only way for you to obtain padding is through your local supermarket, you're a little too large for drynites/underjams, and you're looking for a more 'girly' print than other adult pull-ups, these might be just what you're looking for!
Price and packaging!
These 'diapers' feel a lot like normal underwear, just a little thicker. They're really only good for people who value ultra-discretion over...well....anything else, or those who simply CAN'T get anything better. They're not really usable for a full wetting; you have to double up or stuff them for that, and that can add up over time. With doubling up, you have to pay £1.20 per change, and that's just uncool, considering some premium diapers sell for around that.
Personally, I suggest stuffing them with Underjams with the cloth-like cover removed. The heat/pressure actually causes the Underjams to adhere nicely to the inside of the pull-up, keeping it in place; also helps with clean-up, as it turns into one single piece. Here, have some bonus images to demonstrate.
With a stuffer, this is a workable arrangement, and I love how snugly it's held against my diaper area (males may feel differently, I suppose), it feels very secure. However, at around £1.16/change (with Underjams at £5.10), it's not really worth it to buy these unless you can't buy online. If you do have to purchase some kind of pull-up from a store, I'd say these are marginally better than the generic brands, but not by much.