Sorry to disappoint; all is well. Also, this turbo is presently in my MR2 Spyder, not my (sold) Miata. But 10:1 compression cast pistons and rods VVT-i 1.8 with EFR, so I'll keep going.
With the wastegate wired open, it made 3 psi by 7k.
The rest from clear memory of trends, foggy memory of exact numbers:
With the wastegate on and nearly no preload, terrible boost response (cracking pressure around 3 psi, 5-9 psi peak (never figured out why it varied, seemingly randomly, definitely higher when it was cold out but also some random variation. Actuator rod was coaxial, no kinks in vacuum line, etc).
With the wastegate cranked up a bit, 4-6 psi cracking pressure, 8-9 psi peak boost, 6 psi or so through most of the rev range. Much better boost response, but spikes with on off throttle at higher rpm (EMU as boost controller).
Wastegate cranked up just a teeny tiny bit more, spikes to 12 psi when IAT was very low. Seemed like the wastegate was sticking or something. Never found the issue. Might have been related to using an EMU as a boost controller.
Turned wategate back down, ran MBC. Not even remotely satisfied.
Bought turbosmart eboost street. Not impressed. Was under the impression it was a closed loop controller with rpm compensation when I bought it. It has a lot of features, but almost none of them actually did anything useful.
I say did, because I fit right in around here....
I took the shift light output and ran it into a relay. I used the relay to trigger the external map switch on the EBC. I setup the first map as an up to 3500 rpm map, with gate pressure of 7.8 psi. It switched to a little lower duty cycle and a 3.4 psi gate pressure after 3500 rpm. This works great for 2nd and 3rd at autocross, and occasionally hammers the overboost protection in higher gears or up steep hills (if I go WOT between 3k and 3500 or so). When it falls back to wastegate only, it never drops below 6 psi or so, so for now I'm living with it.
Conclusions: running the low boost can from borg-warner and no boost control is not a smart move. You could have the same boost response out of a T25 from a wrecking yard. I have yet to run proper EBC, but what I have is still worth the money over previous Garrett options I've run. I'm running a full 3" with a cat and a Borla muffler. At 1500 RPM in 5th, it will build 2 psi by 1600 rpm. Under high load it makes full boost before 2400 rpm. Responsiveness is good enough so I don't want more by about 3800 rpm, and good enough so you'd be hard pressed to tell it from a bigger displacement engine by power delivery alone by 3k. I still have VVT-i and throttle transient tuning to do that should both really help spool, but it is already better spooling than a Gt2560 on an 01 VVT miata, so it isn't a high priority.