Sad to say but right before my 7ooR bites the dust it actually performs better.
I've had 3 700's in my 89' IROC convertable
The original died when it began to clunk hard into 3rd, then I had a "performance rebuild" the mechanic told me he put in a stronger shift solenoid and "corvette servos" after 30,000 miles it began to perform differently, shift points changed and it seemed to be giving me more power to the wheels and better throttle response,way better. Then it died. I took it to a reputible trans shop known for building street and drag trannys. I got another "performance rebuild" but this time with an aluminium sprag. 30,000 miles later the same issue of erratic behavior but better performance. I don't get these tranny's!
Typical characteristics of my 700R:
O/D: 1st to 2nd to 3rd shifts hard. 3rd to 4th shifts soft with the infamous eratic 3rd to 4th to 3rd and back "highway punch" (very annoying). Downshifts all soft.

Drive: 1st to 2nd to 3rd shifts hard. Downshift 3rd to 2nd soft, 2nd to 1st hard with clunk sound.
Shiftpoints at full throttle mid yellow line about 5000 rpm.

Now the trans shiftpoints are at 4000 rpm and won't go into 1st unless I shift it into 1st and back to Drive, however it feels as though im getting direct power from my 305 which is good. Seriously it feels like im getting a small nitrous boost. Possible torque converter issue? What can I do to get the trans repaired but keep that power?

 

I never heard of a shift soliniod or an aluminum sprag for a 700. Maybe try a shop that won't BS you so much.