I had started to get back into electronics over the past year, but a number of other projects and hobbies kept getting in the way of it. I built a little 720k last year and did a few upgrades like high temp, low ESR panasonic caps, 2k 10 turn pots, 1% resistors, and decent quality diodes. I also polished up the heat sink and used some of my better quality thermal grease to mount the TO packs. I have to say that its a great little PSU for the bench, but of course it does lack a panel meter as well as adjustable amps. I started to draw up some plans on adding a load circuit, and panel meter, but like I said other things just got in the way. Its something I still want to go back to as this little PSU is housed in a great, all steel case with a good paint job.
I already had a couple of good bench PSU's, but I wanted to make one that looked good instead of just dumping it in a plastic project box. Thats why I picked this one. Its worth it if you are willing to pay the money and time in adding the extras. Otherwise, you will be far better off spending $100+ on a better name brand used bench PSU or more on a new one. If Elenco had just kept the panel meter, this would be a great little starter PSU for many a hobbiest. Most of their older PSU's have meters and are current adjustable. The two main things the 720 has going for it are the nice case, and high quality transformer with silicone taps. Those taps are nice as they wont get brittle with age and heat like the average PVC types. Its drawbacks are the PCB, and the cheap no name components. The PCB has these ginormous pads that are more like big ground planes and they suck up all the heat when you try to solder. On top of that, they are not pre-tinned so you will have to take care of that first thing. I mean, every single spot on the board is several times larger than it needs to be. Its like a PCB for people who are almost blind. The one advantage is it keeps everything spaced out for better cooling, lol.
So make sure you get one or two decent PSU's first, then start playing with your parts bin to make a little one. Once you have that down, then work on modding one like the 720k. You will be much happier that way and you will always want a few PSU's available at the ready.