This is not a bad grinder in its price range. I believe the DCG-3 is no longer in production, but successive grinders look fairly similar. It's a burr grinder where the beans fall from the top, and get expelled out laterally to the side into the ground receptacle.
On the good side, the grinder is multi-purpose, and can be set from french press and drip all the way down to pump espresso and even Turkish. There are many grinders in the <$100 range that cost much more than this unit, but cannot get down to a fine pump espresso grind, much less a Turkish. The improvement over of a $20 blade grinder will be extraordinary, and any such former blade users will be very happy indeed. Users of economical steam-pressure espresso machines may be happy, but if you own anything more sophisticated such as a pump espresso machine of any type, you should consider a much better grinder. Casual drinkers (non coffee fans) of office drip or french press machines should also be happy enough, especially when comparing to blade grinders, or when comparing to the taste of pre-ground coffee. Serious drip and press fans however will find an unacceptable amount of dust and small particles in the larger sizes.
The receptacle area has an inner lid for the purpose of levelling your espresso measuring spoons, and might be a convenient feature for some users. The all-plastic construction is typical in this price range, and even after many 4-foot table-to-floor drops over the years, and other kitchen abuse, it is functioning fine. Therefore it may look cheap, but it hasn't broken in perhaps 5 years of ownership and nearly daily use. This is pretty impressive at this price point.
The operation is via a toggle on/off switch, and it can be conveniently operated with one hand. Even the grind setting can be operated with one hand, if the grinder is set on a flat surface so that the rubber feet and the unit's moderate weight can hold it still.
On the bad side, unrelated to this price point:
The coffee receptacle has a opening lid at the corner top, but if you wish to remove the entire receptacle, you must push a white release button on the side. This button is extraordinarily tough to push, and even two-handed, it always throws me and requires two or three attempts before I can release it. The release button is very poorly implemented.
On the bad side, but common to this price point:
Dust and grind inconsistency: There is a lot of coffee dust generated by this unit, and eventually will cause the machine to slow down. In cases of oily coffees and fine grind settings such as Turkish, this may even mean that the grinder will jam completely. Opening the unit to clean the burrs requires complete disassembly of the unit, and it is not easy with the power cable and various parts falling out of the plastic casing. More conveniently, I found that sticking a small knife or chopsticks in through the grounds exit area was a way to clean it-- the chopsticks could clean the side of the rotating burr, and the edge of the knife could be slided under and over the burr to dislodge the slowing layer of dust. All in all, you would be happy enough for a comparable companion espresso machine (steam driven), and it may even keep some new owners of pump driven machines happy. I would certainly take the DeLonghi for a pump espresso machine over a comparably-priced burr grinder that cannot even grind this fine.
The dust is also a messiness problem. It gets everywhere and will coat the spoon leveler, and the inside corners of the grounds receptacle. If the receptacle was rounded, rather than with rectangular corners, it wouldn't be prone to trapping quite as much ground, but even the flat surfaces will be persistently covered by coffee dust. Over the months, the oils in the dust will darken and yellow the plastic of your receptacle, making it look dirty even when it is clean. The dust will also coat the small opening that is the exit point of the grounds from the grinding area, and will even block it completely. Therefore lifting the plastic lid off of the receptacle to access this exit hole will be at least a weekly excercise, and will result in dust falling over your counterspace on a regular basis.
Motor speed: The DeLonghi's motor and burrs spin fast, typical to this price range. This means a fairly loud noise, especially with the plastic build of the case. Putting the top lid on the coffee bean area (hopper) reduces noise significantly, but it will still be quite loud. (The lid will also prevent coffee backspray from the grinding area's 'popcorn popper' effect). Also at this speed, the coffee will be heated and it will burn slightly. Compared to grinders at the $200 range, the taste difference will be drastic and easily noticeable for any type of coffee preparation. However, compared to a blade grinder, the DeLonghi is of course astronomically better.
At this price range, you should make sure your grinder can grind fine enough for your espresso machine. You should be able to produce a grind that you can tamp that will pretty much jam your espresso machine-- thus you will know you can grind on both extremes of fineness and coarseness, so that you can adjust to the perfect setting in between. The DeLonghi will definitely be capable of this.
However, compared to what you will get in a grinder in the $120 + range, there are certain disadvantages: grind consistency, noise, heat degradation of grounds, dust. But in its <$50 price range, the DeLonghi is definitely worth considering, and if you are upgrading from a blade grinder, you will be extremely happy. If you can find another grinder in this price range that is less messy (dusty) yet can grind well enough for espresso, then get that instead.