I have a couple of speedy's in my kits.
It is really easy to use but you have to practice.
The working end has to be pulled tight against the payout end to lock the stitch.
You get a couple of needles in the handle, while it's a little course the lock stitch is suitable for strength, but can look a little crude.
The spool includes a fair amount of waxed thread.
The alternative is a sail makers palm found in marine shops,
which of course is in my big kit
Also you can find nylon thread which last forever and doesn't rot.