If you're looking to get it with a plan, Maxis, Celcom and DiGi all are offering plans with purchase of it. Which one is better is really up to you. DiGi offers the Lumia 800 starting from RM1099, Maxis at RM799 (6GB+24-month contract) while Celcom offers it from RM998. DiGi seems to offer the cheapest monthly plan. SoyaCincau has a detailed comparison of all the plans. Another option if you want to go with Maxis is to get the phone at retail price but subscribe to its VPI plan. Based on my usage of Windows Phone (Facebook, Twitter, Picture Uploads, Picture Loading, RSS news reading), 250 MB of data is enough. However, I'm not sure the consumption for using Nokia Drive. It will require data to download new maps and search directions if I'm not mistaken. But you don't often use it anyway. The Nokia Lumia plan they offer is a little steep in cost for those who have a budget in their monthly mobile spending.
If you're looking to get your first Windows Phone here, the Lumia 800 is a great choice. As I've only had my HTC Windows Phone for a little over a year, I'm still contemplating about getting it. But isn't it a beauty??