i have had this done, as had my OH, sister and many friends!
to be honest, it is the best thing i have ever done (outside of getting married and awaiting this baby to arrive!!)
i was really blind and it is just amazing to get out of bed every day and not have to worry about trying to find your glasses, paying for new glasses, worrying about eyes drying out with contacts etc.
long story but i ended up in south london and my glasses ended up in north london and i had no spare contacts. my friend had to literally lead me through the streets of london to go and collect them.. it was so debilitating and scary. i couldn't see where i was going... nightmare. i came back from london that evening and rang and made an appointment to get it done the following day.
to be honest my eyes did deteriorate a little bit (i went for plus .5 to minus one) over the space of the first year but i went back and got a top up 4 years ago, a year after i got it done, and they are perfect since. the consultant said that it can happen sometimes.
HTH. let me know if you need any more info!