The quality of M & S knickers is appalling now. The material is so thin that it has ripped when removing a pad with adhesive. And after a few washes my knickers are almost sheer with elastic so slack I need to wear trousers to keep them on. Wearing a skirt or even shorts I've had to yank them up every time I move. And I can see my pads through them which isn't great if I wear skirts or A line shorts.
The midi knickers have gone from their range too. High Rise Shorts are not the same Midi cut because they have lowered the leg to give boyleg shorts but they have also given up the real estate of a comfy wide gusset and for many of us who wear pads, even mini pads overhang the gusset. The shape is all wrong for anything above a UK 12. But also because of the way they're shaped, pads don't stay stuck on the gusset. They move, roll and even drop out the shorts legs (especially now they've redesigned TENA Lady pass too to that are shorter, thinner and unstable).
For the past few years I have been wearing Sloggi knickers. I like the Sloggi 24/7 Cotton Midi Knickers. Really comfy and fits to standard UK clothing sizes (I take an 18). However, they are discontinuing this range and moving into non cotton microfibre/synthetic ranges and styles that rival other sporty style underwear companies like Boody etc.
Sloggi do have a Basic+ 95% Cotton Midi Knickers and they are really comfy for average people. But not as low in the legs as the 24/7 and I have a big sticky out mole on my thigh/hip just where the elastic is on Basic+ and it gets cut into. If you don't have a mole near your knicker leg Basic + is just fine.
In general though, the quality on Sloggi has also declined. I have a pair on today from 2020 and they're still thick cotton and not fine or see through. My last Sloggi 24/7 are not quite as dense cotton as this so not as hardy and the dye faded more quickly. But Sloggi are still way better than current M&S and the elastic is strong.
I still have some old M&S Midi knickers from 2014 and they're still better than new ones. I change my knickers several times a day and have about 50 pairs at least so each pair foesnt get over worn on a rotation. Newer M&S though, they are getting worn out quickly after just one wash and wear.
Somebody on my own knickers post about this suggested another brand that does good briefs called La Marquise and they have a cotton range.
They also suggested Innersey and Wirarpa on Amazon. I have tried them but in my size they have widened them at the hip to size up, but the cut on inner groin doesn't suit me because it's too high and exposes my privates area each side. And the gusset is too narrow for a TENA lady mini pad.
I have tried George (Asda), Tu (Sainsburys) and Next cotton rich midi knickers and they're so thin it is like wearing nothing plus the usual problem of a gusset too narrow for a pad in the size 18. And weak elastic that doesn't even meet at the side seams indicating poor quality control. I like the legs to be around my actual legs.
The market thinks it's catered for me by having loads of full briefs. But I'm 5 ft and those kind of briefs go over my stomach over the bottom of my bra, and some styles can reach almost to my armpits. I have an abnormally short torso. Midi knickers go over my belly button and up over my waist.
If I discover any other alternatives, I'll try to find this post and update you. In the meantime try Sloggi for their Basic+ or look out for last stock of their 24/7 range.