Ozone (O3) generators (aka ionisers, negative ion generators) come in several different sizes and two main types.
Corona discharge types generate O3 by exposing oxygen molecules to a high voltage field between a pair of electrodes or from a sharply pointed conductor, also with a HV charge applied. Corona ionisers also create nitrogen oxides, which combine with humidity to form nitric acid- effectively acid rain.
Ultraviolet (UV) ionisers use a special UV fluorescent tube to make O3 from O2. UV types do not create nitrogen oxides.
Corona ionisers are very cheap to make, compared to the UV types. The small, desktop sized ionisers which sell for $30-80 are usually corona type. They also have rather small power supplies compared to more serious corona discharge ionisers, which have a power supply with a transformer ore like that found on a commercial neon sign (about 15,000V @ 20-50mA).
The units available from the places you mention are more likely to be 'toy' ionisers which will make a little ozone-y sort of smell if you put your nose up to them, but are not generally rated in terms of how many milligrams of O3 they make per hour. OK to freshen a musty office in a climate controlled building, not so good for knocking down the scent of a grow op.
Corona ionisers are very effective at killing scents, but due to the NOx issue, they should be used in the exhaust duct only.
UV ionisers can be used inside a flowering area, but prudently. They are also very effective scent killers, so effective they will de-scent buds still on the plant if O3 levels get too high. However, absent the NOx issue, you can also take advantage of the fact that O3 kills mould spores and bacteria and use them in the flowering room air.
I have a deliberately undersized (but not much so) UV ozone gen in my flowering area. It is placed near the room's exhaust duct. It runs 24/7, but with the high airflow through the room, it is not capable of making enough ozone concentration to burn leaves nor de-scent buds. However, there's enough constant O3 that the exhaust is well de-scented. O3 levels come up high enough to be effective against powdery mildew and bud mould/rot when the exhaust is stopped. Circ fans in each corner of the room help even out the concentration.
If you're going to use an ioniser, make sure you're getting something big enough for your job and that you use it in the right part of the op for the type that it is.