A serious collector will have dealings with the 08 caliber movement, as stated descendants of the early 38xx quartz movements of the seventies. These movements however were subdivided in the SQ, QT, QR and QZ quartzes. They were the JDM (Japanese Domestic Market) watches made around 1971-75, while the export models were mostly labelled SQ 2002, SQ 3003 and SQ 4004.
The highest quality and the most expensive of these 38's were the SQ & QT (with tighter specifications - 15s as compared to QR's 20), then the QR and finally (much later in time as well) the lowly QZ. But remember, at this time there were no cheap quartzes so even the lower grade QZ was more expensive than the average mechanical watch.
After 1975 the 38QR does not turn up again in any other series and dies out as such; it is depicted lastly in the catalogue of 1975 - right next to the identically priced 08QZW/08QZC - that would be calibers such as 0842/0843. It is evident then that these 08's are the descendants of the 38QR. What a conclusion to see these presumably simple quartzes elevated.. Of course they already looked the part.
We are not done here however, and it does not get any easier with the 38QT, which evolves in 1974 into the other 08 caliber, the 08KQW King Quartz series - and, for a year or so, into the elusive 08QTC! That would be respectively the King Quartz 0852/0853 and the Quartz QT 0823.
The 38QZ finally is introduced in 1975 in the 09 series with a 15/20s specification. To conclude, there was never a model year where all these designations existed at the same time but it is evident that the SQ is better and more expensive than both the QT and QR. The cheapest QR of course was more expensive than the QZ at introdution but this compares 1971 against 1975 where there probably has been significant price erosion for quartz watches. However, with more or less the same specifications and a four year difference, the QR would have had the higher market positioning, just below QT.
Some stats are printed below, between brackets the seconds per year:
1974, 08 series, 0822 (15), 0823 (15), 0841 (15), 0842 (15), 0843 (10), 0852 (10) and 0853 King Quartz (10)