Nell, I had an epidural with DS1 and gas with DS2. In my experience the gas (or no drugs at all) is the best option. Sure, you have more pain during the labour, but it means that you can get into any position that is comfy instead of being confined to bed. Also, you are mobile afterwards and don't have to have a catheter which introduces the risk of UTI. I felt SOOOO much better after my 2nd labour (and I was really sick for 4 days beforehand) than my 1st labour - the mobility and lack of drugs in my system made such a huge difference. If you can get through without an epidural I highly recommend it - you will feel better for it after the birth. Also, it is a very empowering feeling to do it without the drugs. Best of luck to you whatever you decide.

PS I also recommend the book New Active Birth - it is great for understanding how positions affect labour.