We've used them 4 times, we got the voucher in the Bounty packs for a free sitting and free 12x10 pic.
Each time though we have spent £100-200 on additional pics.
Your free pic will be lovely, BUT its usually quite a basic shot against a coloured background. They then go on to bring out bubbles, balls, flowers, petals, dress up things etc and some of the action shots you get are fab and hard to resist! Generally they take 30-40 pics and you go away for 15 min while they edit them (some are B&W, some group a few similar pics into large photo's). You then come back to chose what you want and if you picked them all it would be about £800!
This time we spent £180
and got 1 12x10 (free pic) 7 8x10's, 1 20x20 (has 4 smaller pics in it) and 1 20x10 (has 3 smaller pics in a row). You can lower costs by getting them unframed and also not done on canvas.
You'l have great fun, just have a budget in mind and try and be strong and stick to it. We have far too many pics of Caitlin and simply dont have the wall space to keep them all up now!