Barristermum - take all the free advice you are offered, but then go and think about it before parting with cash!
Top tips for pushchair buying:
Will you mostly walk or use a car? If you walk, single handle you put both hands on rather than the buggy-type handles is more comfortable to push. Also, bigger wheels are better for a lot of walking, swivel wheels can be a pain except round the shops.
If you are using a car, how big is the boot? And how often will you need to put the pushchair up and down? Some are easy to fold, others you need to almost dismantle - get them to show you in the shop.
Think about punctures! If you get one with pneumatic tyres such as some of the three wheelers, think if you would be happy to pump up/repair the tyres if you were out for a long walk?
Back to fitting in the boot - some 3 wheelers have detachable wheels to put them in the boot - great, but what if you've been out in the mud? If you don't like getting your hands mucky this may not be for you!
If you use public transport, how easy is the pushchair to fold? Can you do it one-handed? (Some do advertise this) Will it stand on it's own when folded?
Do you really intend to use the pushchair long-term, or are you likely to swap to a lightweight buggy after 6/9 months? A lot of people I have know have spent nearly £500 on a pushchair, found it too bulky/heavy and then bought a £50 buggy!
Where will you keep it when you are at home? Do you have an understairs cupboard you plan to put it in, or will it live in a porch or garage, or will it be in the hallway? Think about how much space it takes folded (and rememeber the muddy wheels...) If you intend to put it in a cupboard, would you really do that in practice? When yo are knackered and just want to sit down? Also, if DD/DS asleep, can you just wheel it in and let them sleep? Does it fit somewhere downstairs that you could do that? (I have bought a cheap shower curtain to throw on hall/dining room floor to wheel it onto. Shower curtains are a good tip for just about anything - I bought a fabric one so it was less skiddy that PVC/shiny fabric, cut it in 4, and used it as highchair mats - easy wash and v cheap. Have large one that goes on table when painting etc)
Carrycot - if you go for a big system (I think like the Silver Cross Sleepover but could be wrong), some come with rigid-sided carrycots that can be used to sleep in - this would mean you don't need a Moses basket or crib, and you have something to take to peoples' houses for the baby to sleep in.
How important is image to you? I saw a prog on the BBC some time ago where they made a couple road-test a Bugaboo versus a Mothercare pushchair - they actually decided to keep the Mothercare one as the Bugaboo had several features they didn't get on with (unfortunately it was so long ago I don't remember what - might have been lack of basket or something)
Don't underestimate the irrational power of want rather than need - I have bought a second-hand Silver Cross pram for this DD3 or DS - I have always wanted one and I just had to have it. Have now got to walk to school to justify it but that's worth it (and better for the environment, too).
My personal experience:
Had a Mamas and Papas Pliko for DD2 - thought it would be sensible as folded small and I had a lot of running around to after school clubs etc to do - actually hated it as the handles always felt "wobbly" to me. A lot of the umbrella fold systems have plastic handles on top of the metal tubing and they just felt awkward to me (Bebe Confort Loola is the same) Also, DD2 was facing away from me unless I put her in the car seat on it (which is not good for babies to stay in any more than necessary) - think the new models have changed this, but be aware that it feels lovely to be pushing your new baby and looking at him/her rather than everyone apart from you seeing them!
Friend bought a Quinny Zapp for her toddler - very easy to push but a sod to collapse as you had to dismantle it, and you couldn't carry it folded unless you put it into its travel bag. Also, the 3 wheel design meant it was quite wide at the back so she was forever clipping doorways!
Maclaren Volo - only suitable for sitting up age - about 9mths plus - as no recline. I love this buggy - best lightweight buggy I've ever tried. It is very light - until she was nearly 3 I could lift DD2 up stairs in it if she had fallen asleep. Could just about do it now if I wasn't pg! Has a strap so you can sling it over your shoulder to go up stairs/escalators etc. Easy to fold. I go to London a fair bit and bought this specifically to cope with the Tube. Narrow enough to wheel down the carriage of a train, too (except for getting past the person who dumps their briefcase in the aisle...)
Anyway, that's a pretty long post but all I can think of for the moment. Even though you may feel daft in baby dep'ts when all the other customers are looking like they are about to drop, you really need to give it a lot of thought, and make the assistants show you everything - putting up, taking down, fitting car seat if applicable.