I had been using a Whale submersible pump to top up my fresh water tank from an aquaroll, but now it has died and is not repairable. A new one would cost me about £40, but I see on Ebay similar spec Chinese pumps for £6 or £7 postage paid. A massive differential which seems to override my desire to buy British where possible. Has anyone bought a cheap Chinese pump - and has it worked successfully ?