Hello
On 8 to 10 years old machines, is it necessary / interesting to have the last kernel in force? An LTS kernel is enough I think? 
I wonder because on one of my machines, each kernel change takes quite a long time to install … and it annoys me to wait …
What is your opinion?
Thanks for your opinion.
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If you have older hardware and only want a single kernel, I would recommend LTS.
Of course, generally, I would recommend having both.
I use LTS whenever I can. If the hardware isn’t new enough to need the newer kernel than I get tired of the new kernel every 15 minutes nature of Arch so stick to LTS so at least it’s only every day or 2.
Install both, use the one which works better.
How do you know which one works better? Try both of them. If there is no difference, then it doesn’t matter which one you use. 
Keep both installed, just in case.
Thank you for the answers. I installed the LTS kernel and it works fine, I didn’t notice any difference.
I will stay on this LTS and remove the “normal” kernel because like tlmiller76 I’m tired of kernel version changes that don’t bring me anything more.
Normally the LS should be more stable too.
Have a nice day.
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You should keep linux installed, just in case something happens and you can’t boot linux-lts. Such situations are rare (a bit less rare if you use DKMS drivers), but having at least two kernels installed is a good idea and it costs you nothing (except a few MiBs when they are updated).
If the frequency of updates bothers you, do not update as frequently. You don’t have to update every day, once a week is more than sufficient.
Yes, it can be a good solution. I update every day and sometimes even several times a day.
However, when I don’t use my machine for several days, everything still works fine !
@Kresimir pointed out the DKMS. To use it, you also need kernel headers, so you’d want to install
sudo pacman -S linux-lts-headers # for linux-lts
sudo pacman -S linux-headers # for linux
In addition, replace some packages with the dkms version.
For example, if you have package nvidia installed, that can be replaced with nvidia-dkms like this:
sudo pacman -R nvidia
sudo pacman -S nvidia-dkms
I also use machines of a similar age. Where possible, the linux kernel will run, if this is not possible, then linux-lts. I usually install both.
Ah yes, the age old question. . . I use the LTS kernel and have for years. Generally, I would say, if you’re not running an absolutely brand new computer, and you don’t know why you should or shouldn’t use a specific kernel, I would almost always recommend the LTS.