I'm sorry that you had such a bad experience with the lastminute.com secret hotel you choose. Nevertheless I don't agree that you should well clear of them. If you spend some time on the net and do a bit of research you can nearly always pin down the exact hotel and I made some good bargains on beautifull hotels. Although I have to say that I only used it for London.
But 133 Euros inkl. taxes for a double room at The Mayfair in London is what I call a good deal and that was through lastminute.com Top secret hotels.