I'd just like to add my experience to this thread rather than starting a new one. After being on the Pill for 4.5 years I changed to a copper (non-hormonal) IUD.
I only had it fitted last week and due to not ovulating for the past 4.5 years my cycle will be screwy for a while but I feel great so far. It lasts 5 years and does not use lactose/hormones as the BC pill does. It is more effective than the Pill and condoms and once it's fitted you pretty much forget about it. You need to check the threads (they curl around your cervix) once a month to make sure it's still in place and obviously it doesn't prevent STDs so it's only for monogamous long-term partnerships but I would really reccommend it.
The fitting is uncomfortable, make sure you've had a good breakfast and take some painkillers beforehand, and they tend to want to fit it on your period as your cervix is a little more relaxed and that way there's no chance you're pregnant.
The doc inserts a speculum, cleans your cervix and rubs numbing gel on it. They then sound your womb using a metal rod. This measures the depth of your womb and lets them know how far to put the IUD in. This is unpleasant, it causes your cervix to twitch which made me feel a little woozy, hot and unwell and caused some cramping of the uterus. Once done the IUD is placed inside you - more uterine cramping - the speculum removed and the doc gives you a quick internal exam to check it's in place. If you've never had one this involves two fingers inserted up into the uterus as they push down on your belly. It's painless and over fast.
I then laid on the bed for a while to recover, the cervix activity can cause fluctuations in blood sugar (hence my porridge breakfast) and slowly got up. I bled slightly more than usual and had some cramping but none so bad I had to take painkillers (but I am pretty stoical about pain)
I've checked my strings twice since having it fitted (it's best done sitting or crouching) and they've curled neatly around my uterus, which feels a bit like the tip of your nose. The copper IUD can cause longer, heavier, more painful periods but often your cycle regulates after 3-6 months. I haven't experienced this yet - as I said I'm still recovering from BC pills so I may not ovulate for ages - but I've had no spotting or cramps since finishing my period.
If anyone has any questions post/PM me, I am a big fan of this method of birth control