In my experience of > 35 years cycling - and especially if you run Continental GP 5000 tires - there is no other choice in tubes... Perfect match to GP 5000s, providing light weight, high quality, long lifetime, and more resistance to punctures and flats.
I bought these two tubes for touring. They were basically worthless as neither one would hold air. Having to pump them up every four hours due to leaky valves was a real hassle. I will never buy Continental tubes again.
The Continental Road Race tubes are a high quality product for road cycling both training and racing. I use them with my Continental Grand Prix 4000 S II tires. One of the best things about the tubes is that they come in a variety of stem lengths. I have two sets of deep rim carbon fiber wheels on my road bikes and being able to get the longer stem is a key feature of this product. The tubes are long lasting and are great when paired with almost any wheel tire combination you have. Highly recommended.
I run 27x1 1/4" tires on my daily commuter bike, a 1971 Schwinn Super Sport. I have had trouble with tubes failing from the stem tearing at the base, probably due to running 700c tubes on 27" rims. I have been riding with these for several weeks now without incident. I feel confident that these will not fail me some rainy morning when I'm running late to work, mainly because I trust Continental's sterling reputation.
I use these tires for my road bike. I have purchased cheap tubes in the past and have paid the price for it. Continental tubes cost a bit more, but seem to hold up, help avoid pinch flats, have better valves and in general give confindence.
When they say "removable valve core" they mean "core outer gage of the exact same thread and diameter as the valve stem". have not managed to refill them without disconnecting the valve core and causing a decompression (sometimes with the fun side effect of shooting the damn core out) once, either with a threaded pump or even just unscrewing the valve cap. incredibly frustrating to use, regardless of tube quality.
Waited about 2 months for these to return to stock since I like these tubes. I use these on a Seven tandem with 700x28 tires and find that running a slightly larger tube in the 28mm tire gives excellent performance. I do not like to over over inflate a smaller diameter tube. Of course, I coat the outside of the tube with talcum powder and always powder the inside of the tire. I find that this gives extra slip when inflating the tube and prevents creases or folds that can cause an air leak or a heavy spot on the tire.
I bought a couple of these tubes to use in an old school single walled 27 wheel. I liked the stem size. At 42mm instead of 48mm (too long) or 32mm (too short), these were the goldilocks size, just right.
But what impressed me most is that they held air pressure better than most any other light weight tube I've used. So I tried them in my 26er and had the same results. Before I knew it was was switching my 700C wheels as well.
I know many will say a tube is a tube and only as good as the tire that surrounds it. But for me, the light weight, perfect stem size and proven less air lose makes this my choice for tubes going forward.
Sure, it is just a tube. But have you ever really considered the gravity of your decision when selecting a tube for your bike? Some tubes are made from crappy parts or fall apart. I cannot count the number of times that Kenda-made tubes have had valve stems which bend/break or generally deform. Continental tubes cost a bit extra money because they are quality parts. These are not high end frou frou race tubes which need to be treated with extreme care and cuddled throughout your ride. These tubes are for when you want your tire to stay round, not break valve stems, and generally be the last thing you worry about. This is not to say that there are not downsides to this tube. If you run over a thorn, some improperly disposed glass beer bottles, or if a youth decides to slash your tire with a butterfly knife, then it is likely that your wheel may go flat. This is after all just a bicycle tube, not an indestructible ring of fury and speed. But, I am confident that this is the tube for me, possibly for you. When in stock, it is the first place I go.
TL,DR - Quality tube at decent price, won't fall apart.
I use these on my road bike with gatorskins tires,have not had bad experience with them. valves are strong don't break . value rating is 3 because everything is too expensive.