I have been collecting quartz watches avidly for quite some time and opening cases of quartz watches can be quite an eye-opener. Some watches that look fine on the outside sometimes have crappy plastic movements of the no-name variety, while others that seem to be as cheap as chips will be found sporting a perfectly good Miyota metal movement. I agree with xellos99 about the early Seiko quartz movements, which have a number of jewels and seem to be of good quality, and the upmarket ETA quartz movements. I must also just reply to Bluehaze284 here, to confirm that many quartz movements contain rubies, some of them containing a considerable number of jewels.
It is sometimes said that quartz movements are somehow "soulless" when compared to mechanical movements, but I am not sure that I agree with this. It is true that there are certain "workhorse" quartz movements that seem to turn up time after time in all sorts of watches, but there are other movements which give one a little lift when they are encountered in a watch. Certainly, at the top of the quartz movement tree, there are some real beauties, and these include hand-made movements that are a genuine part of the watchmaker's art.
For me, one of the real "victories" of the quartz era has been the ability to produce inexpensive yet effective analogue chronograph movements that can be used on watches down to a tenth of a second or so. These movements have been widely used to produce many very nice watches, and the cost difference between a perfectly good quartz analogue chronograph and a mechanical example is very high.
I have met so many different quartz movements in watches, including the various examples from Seiko Group, Casio, Miyota/Citizen, Ronda, ETA, etc.. that I cannot say that I have particular favourites among the cheaper varieties from these firms. I do have certain watches that contain upmarket quartz movements, and these I jokingly call my "deep quartz" watches because although they are powered by quartz movements, they still have "soul".
I have mentioned analogue quartz chronographs, but one must not forget the digital revolution that went hand-in-=hand with the development of quartz movements. Some of the best quartz movements are to be found in digital watches, or combination analogue/digital watches.
So finally, what do I look for in a quartz movement. Well, I like to find movements with metal casings and with company and calibre details impressed on them as well as country of origin. Also, being old-fashioned and having a mechanical heritage, I do like to see jewels in my analogue quartz movements, preferably 5 or more. Having said that, my experience of quartz watches seems to confirm the idea that some of the cheaper no-jewel quartz movements are surprisingly reliable and accurate, and as long as battery leakage, water-ingress, and overt damage is prevented, even cheap quartz watches can go on working fine for many years.
So I would say to collectors, never pass up a good quartz watch at the right price, even if like myself, mechanical watches are somehow always at the heart of your collection.