Measurement was at 1KHz.
The big problem with this device is power dissipation. If you keep the JFET around Idss, Vce of the cascode device should be under 10V. ~100mW is all this SMD case can take. The Vcemax of 50V is pretty much useless.
Devices from the same tube (I got 100 pcs and fed my whole class) are matched to +/- 10%, so a cascoded LTP is feasible. I've built a discrete opamp with these devices in the input stage, 18 more transistors and 0402 RC's (everything hand soldered) in less than .25 sq. in.
Edit: 1KHz and about 12mA (that is, Idss)
Thanks! Better you and your students than me, hand soldering 0402!
If the construction is similar to other SMD JFETs, the gate lead has high thermal conductivity to the chip. Although it's not particularly convenient to provide a lot of local copper in the plane, one could go up. I'll let everyone know how my multiple 862 birds-on-a-wire construction works out. The small irony is the tempco is so low that a temperature estimate may prove difficult