Bathroom Renovation-water Pipes

[bhr2009]

Hi

We are planning some renovation for our 8 year old bathroom.
We will be replacing some of the fixtures like mixer, taps etc. I would like to know

1. if it is good idea to replace the GI pipes used in floor/walls for water connection.
2. If replacing , what is the type of pipes used now a days for this purpose ? PVC ??

Thanks