I had mine done at M&H a couple of years back. Went in, chose the cleft, discussed what sort of weight/profile/handle thickness/pick-up etc. I watched every process that was involved, and once is was finished I decided what Labels and Grip I wanted.
When I had it done it was worth every penny in the £250 I paid, as it was a cracking bat that is still going strong now (Will be in its 4th season next year). I think it costs about £300 sheets at the moment, but it is a bat that will play extremely well and is bound to last a long time!