Right people, do NOT under any circumstances use 'the complete online pond, garden and aquarium store' to buy any electrical stuff from

They have messed me about from day one with a faulty Arcadia light unit. I sent them a letter along with the unit explaining that the fault was intermittent, and they have sent it back to me today without a letter, email or telephone call.
They have a DESIGNATED testing area for faulty returned goods - how many companies need this if they supply good stuff anyway?
I have rang them numerous times about it, been fobbed off, been told I will get a credit then a cash refund. I rang on Thursday, after the unit being with them for TWO WEEKS, and was told it hadn't even been opened yet. I got the unit today, rang them and the patronizing bloke on the phone - Chris - tells me that it was tested all day Thursday and Friday. As if! We had tested it ourselves with two different makes of brand new bulbs - which incidently work fine with our cheaper Glo unit - and it doesn't work. I am absolutely fuming.
We're going to test it again tonight ourselves and go from there. But I shall be complaining about the poor service I have received.
This has been going on for weeks as we tested it ourselves over a week or so, just to make sure it was faulty before sending it back. We had a huge hassle getting the hood off our tank as well to do it.