Mark, check out the SOM 16k No-Limits spools, I use these on my 8-10k SW stellas and get 260m of PE8 GTmax on if packed really tight. Not sure if they go on the Twinnies though??
Regarding the PE8 SMP failure, only one bad experience for the record, a gt came charging from under the boat and hit the returning lure head-on with about 20m of line out, the line popped fairly instantaneously half way up. Perhaps unfairly or over-cautious, but based on one incident i shelved it for GT purposes after that. It was on a nomad trip at the time so with that cash outlay I was not willing to use it further and went back to GT max which I have never had a similar issue with.