I used a TENS, it worked well for the first 12 hours of hard labour, but after that it annoyed me...

I will use it again though, great for distraction of the pain.

If you get one, makes sure that you get it well before you are due and you know how to put it on (or you birth partner does) and how to control it...
You may not like the sensation when you are not in labour, but it makes the world of difference when you are actually labouring.

Based on the effectiveness of it, i will probably try the water injections next time too