Had a good bit of work done by the dental school. Basically, you go up the first time (think they are open from 8.30 am) and go to reception. They take your details and you pay €30 and a consultant looks at you and notes what work is to be done. They put you on a list and a few weeks later a student will call you and ask you to come in (they are probably heading on holidays from college now but wouldn't hurt to go up and get registered now so you'll be ready to go when they come back - July I think)
Work wise they are excellent. All the student work is supervised by a senior dentist. More junior dentists would do routine work like cleaning and filling while those in later years would do more high level work like root canals etc. They are all very professional, use the latest materials and methods and in my opinion are better than alot of qualified dentists - because their work is being supervised as part of their training.
You asked is they are kind and patient. I found them to be very patient (they won't rush a procedure) and very kind. I had an especially nice female student dentist (having spent time up in the dental school I now wish I had done dentistry at college)
Price wise there is no comparison. Fillings cost me only €10 each and a root canal was a fraction of the price I'd have had to pay a "real" dentist.
Here is a list of their prices: http://www.ucc.ie/en/media/price_list.pdf
I was seen by a consultant initially and by a very pleasant student thereafter however the work I was having done was on a root canal and I spent many very long afternoons in considerable pain and discomfort having the roots worked on by a student who must have been out of her depth. Looking back on it perhaps I should have asked to speak to the consultant but I didn't; I was going through some very difficult personal things at the time.
I would think though that unless the treatment you require is relatively straightforward ie. fillings etc you would be better off in the hands of a fully trained professional. Just IMO.