The triangle consumer is effectively what will be sacrificed. In many cases the people will take a greater price for the additional hardware options that they get or will take the lower price for the more simple designs. The third part to this is quality, and this is attributed to a number of factors when one truly is seeking an ideal cheap car stereo.
The first of these factors is the design and the brand that is making the stereo. Some stereos have been shown to be rock bottom in price, yet have a design flaw in them. This has been something that in most cases will not be seen in the short term or possibly in the long term. Sometimes it takes certain cars, trucks, or other machines that will expose the flaw. One of the more common is faulty grounding in the stereo, weak plastic parts, or a design that is not suited for modifications. Small companies have fallen victim to the lack of support and will often show this in ideal cheap car stereo designs that are perfect except in the advances that other brands may offer.
Another factor is stability, as mentioned grounding is one such factor. The suspension in a CD or remote signal feed is another that can cause problems for someone that is going to transverse harsh terrain or spends a large amount of time driving. Sometimes the feeds will be unregulated and this can cause feedbacks to the speakers, hence, creating strain on the sound and hardware.
The last and possibly greatest factor is older and used designs. These are usually cheap car stereos that have been already used or are discontinued. Many of these are in perfect condition and can be easily installed by someone that is knowledgeable in this. A number of these are offered through the manufacturer's website or retail stores (if they have a store), and will be labeled as a number of things. The key thing is that they usually have some small warranty and are not sold "as is" where a number of other places will not offer this.
Some have gone to pawn shops or to used auto part stores for a cheap car stereo, yet these are usually the most risky that someone can get as they are not ensured the be working or that they will not put the rest of the car at risk with any issues that they may have. The one problem that any older car stereo will have is lack of proper documentation that can be offered. This is very common with discontinued stereos.