Bagless Hoovers - not at neat as you might expect

We bought a Hoover Alyx TC1183 Cylinder Cyclonic 1800W HEPA bagless vacuum cleaner after we moved into our new apartment. Bagless sounds like a good idea, doesn't it? No need to buy replacement bags, instead you just empty the drum into the bin and you're good to go again.

Rubbish.

Instead, you have to clean the Hepa filter after three or four uses. It's relatively easy to dismantle it and if only it were a question of following the simple instructions to "tap the filter over a bin and rinse under warm water, if necessary". Tapping hardly helps, and although washing under water seems to extract a fair amount of dirt, because the Hepa filter is pleated like an accordion, the dirt gets wedged into the fold and doesn't come out, no matter how much tapping or rinsing happens. It's dishonest. I spent a good twenty minutes of my bank holiday weekend with a screwdriver, scraping the dirt out one pleat at a time.

Before you ask, no we do not have dirt that is untypically sticky. It is normal dust and carpet fluff. I can't believe that Hoover haven't tested this and discovered this design flaw for themselves. Why doesn't the Hepa filter slide off so I can stretch it out to wash out the nooks and crevices?

I doubt I'll be buying Hoover again. My only previous experience with his brand is a washing machine that ended up leaking and the plumber said it wasn't worthwhile trying to salvage.