One of the biggest problems I find with solicitors, is the time they take to do things. It absolutely infuriates me. Some solicitors give the impression they know best because they have sat all the exams and they will do things when they are good and ready. With that in mind, I try and do a lot of ground work whenever I employ the services of a solicitor and then agree a rate beforehand and get it in writing.
Word of advice. always put everything in writing too, either via email or letter and if you ever do call them, make notes of the content of your call, the duration, date etc. Also, if you send them any paperwork, photocopy it, and send a dated covering letter.
You never know when this information may come in useful. I have taken solicitors to task before, and believe me, I wouldn't hesitate in doing it again. I treat them the same as any other service industry ie. if I feel I am receiving a poor service, I let them know.
Always assume the worst, ie that they (the solicitor) will lose something or deny a conversation ever took place. They are no different than many other industries where there is good and bad in the various practices but always be prepared to take them on if you feel the service or advice you have been given is incorrect.