Not a Jensen 65, which is a double acting spindle valve engine with a fixed cylinder, but rather a Jensen 60 (or possibly a 76, the kit form of the 60), which is a nice addition and a very capable little wobbler!
The Jensen 85 is one of only two Jensen Overtypes, the other being the Jensen 35, which is also a wobbler of a somewhat more substantial nature, as well as being a double acting engine.
Yes, Jensen's are wonderfully robust engines and of a quality that is really tough to top in the toy steam world!!!