Thought I'd add my bit, even if I'm a yr behind! Yes, I'm fairly new to Mumsnet & don't post v often - but here's my experience of uselessness & usefullness so far anyway:
Mothercare 1st stage carseat - plastic trim broke away from fabric so frayed within wks. Wish I'd got a Britax 'cos I didn't realise how much use it'd get (ie, not just for car journeys).
'Illexia' pushchair/pram (which I or anyone I know had heard of) - Nightmare thing which was a gift. V basic pushchair with no 'xtras', not even a hood!. The 'shopping tray' was little more than a mini hammock which dragged on the ground if u put anything heavier than 1/2 dozen eggs in! I agree with previous comment about the hassle of having a framed raincover which doesn't fold with the chair.
My sister bought door bouncer ('Lindam' one I think) for her ds. He liked it a lot xcept they had to put up padding each side of the doorframe 'cos he nearly banged his head. I think she also had trouble getting him in/out of the thing.
Bouncy chair - hardly used 'cos ds was either in pram, carseat, cot or on a playmat with gym & when he did go in it, he kept still, wasn't keen on kicking & making the chair 'bounce'.
Boots cold water sterilizer & bottles - Took this lot back after a few weeks 'cos measurements wore off side of bottles. Ended up with Avent kit instead (well worth the money IMO).
I give a thumbs up to Prima Pappa highchair tho' despite being hard to clean. The pros far outweigh the cons for us.
Also got booster highchair, kept at MIL's which is xcellent. This has been everywhere - birthday parties/BBQs etc.
Hope that helps someone.