I always use a regulated supply.
Powertech MP-3017 regulated Power supply 12 V 2 amp. $59.00
http://www.andrewscom.com.au/site-co...section-09.htm
I also use a Powertech MP-3079 12 A one but Andrews have a 20 A one (MP3078) for $99 which seems a bargain to me especially seeing as I bought mine from another shop and paid considerably more for it from memory.