I bought this case after my lovely Mum dropped my shiny new N900 on a gravelly car park and damaged the screen :( I knew after having it repaired I could take no more chances!
I researched the net well before choosing, and I knew the case was a little clumsy with regards to texting (because the flap opens down below the keyboard) but for protecting the phone, it does the job brilliantly.
yes it does make the phone bigger in your pocket, and makes it look clumsy when you bend the case back to hold it to your ear on a phone call, but for me, I don't care. I have had 3 previous N Series phones and all have had similar cases, so I am well used to it. I'm not bothered what I look like, so long as my lovely handset is protected, and it is!
It looks very stylish, despite not actually being leather, but it is made of some other hardwearing material, and after 8 months of use, still looks brand new (as does my phone thanks to this case!). It also has a debit card holder built into the front cover which is a nice touch. The clips secure the phone at the sides (with the phone in landscape position) but do not interfere with the sliding mechanism of the phone at all. I had read that some people experienced paint wear on the phone wear the clips had rubbed, but I have had no such problems. I can only speak as I find.
Would I recommend it? Absolutely! And in the horrible event I lost my phone (!) I would buy another in a heartbeat for it's replacement.
5 stars from me. Very happy customer.