I have a Dunlop power brick (now for sale) and never had any problems with it. Haven't compared it to any others and couldn't comment on hum or 'tone sucking'. Its better the the Diago lump of poo I had.
T-rex Fueltank Classic can power loads of different things and T-rex make quality stuff in my experience. Plus it has a 'kettle lead' fitting, which is more sturdy than most power leads.
Thats my pennies worth :)
