(I'm sorry, I didnt read your original post so closely and wrote all this under the assumption you were a beginner starting out.. but its long and might help somebody so I will leave it)
On an electronics bench supply, specifically, its very nice to have a number of things - one of which is dual meters, whatever their type, analog or digital doesn't matter so much for everyday work, so you can see both current and voltage at the same time. Almost all bench supplies will give you either dual meters or the ability to switch between voltage and current.
Not so frequently but enough times for it to be important, Ive had it happen that some device starts drawing an unusual amount of current and if you are used to what it usually draws when it suddenly starts drawing more you will notice, if your power supply meter shows it to you.
Its even better to have both dual meters and whats called "constant current" adjustment on a supply, which lets you limit the short circuit current drawn by some experimental device to a little bit more than what its supposed to draw. Then the chance is much lower that it could self destruct.
Otherwise, you may not notice it getting hot until something starts smoking or smelling funny and by them its usually too late.
With constant current you can fix a broken device without fear of causing more damage by applying power by setting the constant current first.
Then not only will you prevent any shorts from causing more damage, you can then instead track them down by a process of elimination and fix them.
Thats why a good bench supply is worth every penny you spend on it.
Actually, right now there are some great deals on fairly modern GW Instek (one example is the GPC-3020 triple supply) bench supplies on ebay, they cost a fraction of what anything of similar quality would cost you new, and although there are better deals on old equipment you need to do a lot more research and know what you are getting, and with these particular supplies the risk is virtually zero of getting a bad unit, because many of them are literally brand new or close to it.
If you don't already have all the expensive parts in your parts box to build a decent bench supply you might want to consider getting one of them. For around $50-60 you can get a supply that you can probably use for decades, that would cost you at least $150 new.
You should still build your own, especially if you have some need (high current or high voltage or high precision) and or already have the parts, its fun and a good way to save money, but in practical terms if you are a beginner trying to set up a bench you would likely end up getting a decent bench supply a bit down the line anyway, and now as there still are these used but still quite current units on ebay for a fraction of what they usually cost, and they are a known quantity, (known to be good) I would consider a GPC-3020
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