The Super Rokkor 8.5cm is a very good lens -- nice wide open, and plenty sharp stopped down to 4 or more. It is pretty small, although it is quite heavy, with lots of heavily chromed brass. Like all lenses of its time, it is prone to fog and stiff mechanics. Strangely, it takes 40mm filters, which are harder to find than 40.5mm ones. The original hood is very hard to find. They usually are not that inexpensive, since they are quite good, were not made in large quantity, and collectors like them. If you can find a nice one for a good price, get it.
Note that the the Super Rokkor 8.5cm has the same optical design as the Super Rokkor 45mm. However, it is not a Tessar -- it is sort of in between a Tessar and a Heliar, with a 5-element/3-group design (cemented triplet up front and two single elements behind the aperture). The later Super Rokkor 50mm f2.8, which replaced the 45mm, has the same design.
Cheers,
David