Just to start by saying i am not affiliated with Firefly in anyway but we had such a good experience with them last year i wanted to mention an email i have just received of Firelfy.
They are now starting up routes from Sebang (KL) to Singapore and Phuket. We found them very very cheap and had excellent service although i do know that some people have had issues with them cancelling flights. However for those looking for this routing here is another option just in case.

Lier, lier pants on fire Smeagol! We know that you are the lady furtest left in the picture below(picture of the cast of the hit TV show "Firefly").

http://tiny.cc/opU5n

Now if only i were that good looking!!!

Seriously though we thought they were a great airline!!!

I also recently had a good experience on Firefly (Penang to Phuket) Interior of the cabin was really clean and comfortable new leather seats. And to top it off they give snacks/drinks for free....unlike AirAsia

I've also had good experience - although only one flight - with Firefly. Worth noting they also fly Penang - Samui.