Had mine done recently by Feet First and can't fault their service.
One thing to keep in mind would be that soles go out of stock and it can be a several-month wait (they told me) until they come in again. Fortunately for me, I had a still usable old pair of boots knocking around and as it turned out the wait was not too long.
In all cases give them a call before you put your boots in the post to make sure they have spare soles in stock. La Sportiva have a habit of being hap- hazard on their supply of soles which can cause a long wait / queue.