Same as the lovely Londondrz..... wotcha by the way
We used a Graco which lies totally flat and has lift-out-of-car-and-attach-to-buggy carseat, (only thing is our version's a bit heavy) plus a pushchair only lighter version.
Our pushchairs have come from Kiddicare http://www.kiddicare.co.uk (who are worth looking at for prices by the way, based in Peterborough but do free and very quick delivery). We also have a mega light and largely useless ?15 pushchair
This time I've felt really strongly about wanting to have No 2 facing me when flat in the pushchair (Graco faces out) so have picked up a two year old Mamas and Papas Pliko with car seat on ebay for ?62. I wouldn't usually buy a car seat second hand but I trusted the seller and it is immaculate.
Unless you are minted, don't be persuaded by "fashion". Your child really won't care and if the yummy mummys at the swings in Dulwich look down on you come and find me and we can be deeply uphip together.
If you drive, do you need a matching car seat that can slot into the main body of the pushchair? Does it fit in the car boot? Will it fit securely in your car (if you need to use a seatbelt beware as I spent most of the first 6 months of the life of our son sweating and swearing as the seatbelts in our ancient Clio were too short! My husband was very happy that we "had to" change cars!), will you want a carseat base. Can you fold/pick up the pushchair by yourself (one handed even better)? Can you get it in your house if required? How important is forward/backward facing to you?
Oh and also I belive that Graco make the Mothercare buggies so keep an eye out for the varying prices there.
Hope some of this helps. You will find that now I have remembered my password and have delurked, that I tend to ramble somewhat.... (and I've just realised repeat most of what's already been said.. )