Cheap pharmacy reading glasses can be a good choice as an auxiliary glasses for certain emergencies. This implies using it exclusively for specific tasks and not for jobs that require an extended space of time.
As a general recommendation I would tell you never to buy pre-assembled glasses or other optical or health products in a Chinese bazaar since, regardless of the problems common to glasses of this type, the controls that pass these Chinese imports are almost nonexistent and the quality is usually even worse. If you are going to need a reading goggle, buy it better at the pharmacy or optics. This is also applicable for sunglasses because many false copies circulate without ultraviolet protection as you can read in the post about the false rayban sunglasses
What should I do if I start having trouble reading?
The most important thing is to go to the optometrist or ophthalmologist to perform a review of your eyes. Graduation is one of the parts of a review, but it is always advisable that in addition to graduation you perform a preventive visual health check that is the way to prevent and detect eye health problems that are not related to graduation.
Which alternative is better in my case?
We do not have a single graduation close up, but we have a different graduation for each distance. It is essential, therefore to know the visual requirements of each person because the graduation for the normal reading distance is usually 0.5 diopters higher than the graduation to see the computer, each person having an ideal reading distance different depending on their habits , Height, etc ... I have a published entry on the Ideal Reading Distance Here.
Different choices of glasses close up.
The need for many jobs to combine the vision at different distances (reading, computer, table, attending other people or colleagues), require to adapt the best optical solution to each case hence there are different options of glasses for close.
Monofocal single-reading reading glasses
If you only use a single distance and when you are doing that task closely you do not have to look at other distances (sewing, reading, etc ...) a monofocal reading glasses with anti-reflective crystals will suffice. Of course, realize that this option will force you to remove the glasses as long as you are not looking at that exact distance up close.
Glasses for near and intermediate distance. Occupational Progressives
If you need to use several distances because in addition to reading you have to work with a desktop computer that is further away, the options you will have will be an occupational progressive with graduation for near and medium distance that will allow you to see up to the distance of the computer (or farther Depending on the type of lens). You can see clearly up to 50 cm or 1 meter depending on the type of occupational lens. Further away you will see blurry so many people opt for a non occupational progressive that will allow you not to have to remove them to see from a distance.
Glasses with progressive lenses valid for all distances
If you see well from afar, but you want to have a goggle that you do not have to be removing and putting when you change from close to far and vice versa, your best choice will undoubtedly be progressive glasses. Imagine for example that if you are going to buy something at the supermarket or a store with these multifocal glasses you will not have to be removing and putting, looking at a composition of a product, a price at the same time as seeing a shelf in the middle distance or a poster that Is located far away.
Of course, if you do not have graduation from afar when out on the street will be more comfortable than the ones. Always with anti-reflective treatment and if possible with a custom design to achieve a higher quality and field of vision.