I had to book a flight from KL to London at fairly short notice and of course all airlines were charging a lot, especially for a single. So I decided to try AirAsia which was the cheapest for a single, but was still very expensive. I flew in mid April 2009.
The verdict - the most boring 13+ hours of my life. And I wouldn't choose AirAsia again for such a long haul flight unless I could get a really cheap ticket.
A lot of people think the seats may be small and cramped, but I found them to be fine, same as any other airline. The plane is smaller than those used by other airlines, so there are less seats (2 x 4 x2) and less rows. And because of the layout of the plane, it was hard to walk around at the back.
But I found the flight totally boring with no free entertainment, no route map etc. I don't normally watch films on flights but I like to play games, catch up on the news and watch the flight map and details. So I was bored silly without this. You can pay for entertainment but the sets are limited and ran out before they reached me. I heard some people had problem with their sets and the batteries ran out early. Also the choice of films is limited.
I took a day flight, flying west. The lights were left on the whole journey and the window shades were left up so we had bright daylight for 13 hours.
Airlines advise sleeping as little as possible when flying west, so maybe this is why the plane was kept bright.
Unfortunately I didn't pre-order meals and wasn't able to buy them on board as the only had enough for those who had booked. You can buy snacks and drinks. Water is RM4 (note it's cheaper to buy it in LCCT departure hall at RM2). Mid way through the flight everyone got hungry and was buying food and drinks. By the time we approached London they ran out of snacks to purchase. Luckily I had taken quite a few nibbles with me, but not enough.
The staff work hard as there are less crew than on other airlines.
Several people bought comfort kits of blanket, eye mask and inflatable pillow. I'd got a sarong and jumper with me to keep warm but didn't need either.
The flight was just over 13 hours and we were onboard for more than 14 as we were late leaving KL.
It was the first time I've been to Stansted Airport. I found the bus into London was OK but it took 75 mins which was a long time after a long haul flight. OK you can take the express train but it's more expensive.
Unfortunately I paid a LOT for my KL to London flight as I booked late. I certainly wouldn't fly AirAsia again long haul unless I can get a cheap flight.
See a related blog on http://airasiareviews.blogspot.com/2009/03/air-asia-london-flights-review.html
When it was time to return to KL, I really wanted to avoid flying with AirAsia. But I had the same problem as on the outward flight, in that to buy a single on one of the "regular" airlines cost an arm and a leg, even more than a return. So very reluctantly I once again booked with AirAsia. This time it was a night flight and I was more mentally prepared.
The flight turned out to be better for various reasons. I had prebooked meals, which actually wasn't necessary, nor did I need the extra water I'd taken. I have to say the meals are rather small and I had finished by the time the trolley was only 4 rows away. I was glad I had my own snacks with me. Being a night flight, and a cold one, people weren't ordering food and drinks during the flight inbetween the meals, so there were still meals and snacks available by the time they brought round the 2nd meal. Incidentally the water bottle that comes with the meal is only 350ml.