If you are talking about Impiana Hotel, it should be the one near to China Town and not KLCC. Not knowing that there is a Impiana Hotel at KLCC.
If you want to shop for branded goods, you should go KLCC. If you want imitation goods like watches and handbag, you should go China Town. The watches there is dead cheap. Only RM10 to RM15/pc. Walk around first and do not buy at first sight. Try Vinci shoe shop where they have a lot of branches everywhere. I like their shoe, it is reasonable and comfortable to wear.
When taking taxi there, ask for the price first before you get in as most of the culprit do not want to go by meter and they can anyhow charge you especially if they know you are a tourist.
Any other things you want to know, email me at [email protected]