There's a sucker born every minute.

i bought rainbow many years back. that time around 6000+
still using until today. so many years already tahan lasak. use water as filter and can wwash my car with it also.

i cannot tell u how long phillips will last, but i can tell u my rainbow is more than 10 years liao

Delphi and Rainbow so expensive because of commission.  Granted, they are very good, but at that price, not sure worth it or not.  I heard the salesman gets RM100 each time he can demo at your house, that's why they are so eager to demo.  The demo they will do to impress you is vacuum your bed, and show you how much dirt is trapped in the water.

I use Dyson DC38, 2K+, it can suck my bed just as well.  Smaller and lighter and easier to carry everywhere too.  5 years warranty for the motor.

Even if you use RM300 Philips vacuum cleaner, it can still vacuum drapes and mattresses and pillows.  You just need the kit.

Samsung got one model using double water chamber... one to trap dust, another to filter the outgoing air (I think got HEPA filter too).  So, double the goodness of Rainbow? 

Actually, water itself is not so good at trapping dust, becos dust/hair/dirt are not water soluble...