In terms of playing in London, it really does depend on level and location. I've played on pitches in Greenwich Park, Wansford Common, Raynes Park, Croydon, North Middlesex Club Ground, Ham and Reigate. The pitches all vary. The commonest way to look at it is as follows:
In the early season, they are nearly all slow and low.
This summer, they became much bouncier and came on to the bat better after the dry spell.
After the wetness towards the end of the season, we had much slower pitches again, but this time slightly bouncier.
Very varied, and the location makes all the diference.
You'll probably find that they take significantly more seam than you are used to (I can make a ball pitch leg stump and miss a fish outside off stump, and I'm only playing lower league level), but combined with terribly low bounce.