Among the less expensive drill presses one major variation is the fit of the quill in the housing. My advice is to buy one only in person, after extending the quill and moving it around side to side and front to back. If you feel any play, don't buy it.
Also, have the seller plug it in and listen to it run. If it's smooth and quiet at several speeds you are probably OK. If it is noisy as a freight train, or shakes enough to knock a house down, don't buy it, it will drive you crazy. Sometimes these faults can be fixed but I've seen a few where it was just a bad combination of materials and design that result in a real mess, and could not get them quieted down and smooth .
I have a large floor model Taiwanese drill press , the 'King' brand in North America. It was relatively cheap to buy. It performs well, is very powerful, and is quiet. It had almost no play in the machined parts and has kept this quality for 8 years. However, when buying it and comparing units in the store, the same model machine right next to it shook like crazy when switched on, and had at least .030" side play in the quill when it was extended.
Good luck, JD