For those with foot drop, AFO's are great. I have bilateral foot drop and use Otto Bock WalkOn Trimable 28U23 AFO's. They are carbon fiber, light, cool, and comfortable. My feet don't drop down too much, without the AFO I land flat footed rather than on my heel (most people when they step forward land on their heel and rock forward onto their toes). I found my big toe catching on things and I stumbled forward, sometimes jamming my toe or toes. Biggest problem was if I was barefoot on grass or beach. With AFO's I don't have that problem. I think the AFO's make walking down stairs or down hill harder. As the foot drop got worse, I found I was waking up in the morning and my shins (outboard side on both sides) ached. Doc got me a boot like AFO that velcros on and had a hard rubber sole. They are big and bulky and wake me up. I did use them when I was in the hospital for awhile; they kept my shins from hurting and I could get up and walk with them on. I just got two AliMed Dorsal PF Night Splint. It does the job and since they are not as big and bulky I sleep better with them on. So much for my experience with foot drop.
Leg strength is another problem. While I'm not tripping over little things when I have the AFO's on, I am finding it more and more difficult to go up stairs, step up into a truck, get up from a chair or get up from a knee. I use my arms more to get myself up. Don't have a fix for this problem. I think if you're losing leg strength it's a good idea to be looking into wheel chairs (powered if possible) and ways to cope with getting on with life without walking. Not a great thought but it's what those of us with ALS have to face. Best of luck to you.