We recently purchased the 'BabyDan Configure Gate XXL Black' from Safetots. We previously had the Infantastic playpen which we're keeping for when we travel and for when Emilia stays at her grandparents' house. We decided to get a bigger and sturdier playpen as Emilia is walking now and has quite a lot of toys. I wanted to be able to keep an eye on her and for her to play happily and safely whilst I'll be caring for the new baby. I believe this type of playpen was well priced (£89.99) and I'm extremely happy with our choice.
(This is the old playpen, which has served it's purpose and would probably have stayed as her playpen if we weren't having another baby)