Towa, Tasco and many others offered a very standardized OTA and mount in the 60's thru the 80's or so. I'm sure they sold a gazillion of them. The equatorial mounts were very marginal in my opinion. I semi restored one and still found it unacceptable. The wooden legs were floppy, hard to manage and were very shaky. If you extended them to max height for comfortable observing they were terrible. More steady and solid tho when not so extended.
The OTA's on the other hand seemed to be well made. Focusers, finders, and dew shields were functional and attractive. Optically, I don't have much experience and would like to hear other opinions. The first one I bought had a huge clamshell. So I replaced it with a Carton lens. The second one I owned didn't hold up to the Carton lens so I replaced it with same great results. So I cannot critique the optics of these classics as I've only viewed thru one example. I'm guessing that like Unitron's the optical quality was not standard. Would like to hear other experiences. I will say that the OTA with Carton lens mounted on my Unitron 142 mount is a wonderful performer and is a keeper.