Of course I have been to the Menara, the Kuala Lumpur tower. It's a must when in the city and I have been up the tower on every visit.
I usually take it day by day until I see that the weather is perfect (means for me: no clouds, no rain) and I typically visit in the morning hours.
I have never taken public transport but have walked to the tower from wherever I was, which gives me another nice route to explore.
The last bit is the most sweaty one, up the steep hill. But there is a shuttle which will take you up the last bit, if you wait by the entrance.
While the Observation Deck is nice to visit and about half the price, I do enjoy the Open Deck the most. The price of 99 RM was steep, but absolutely worth it. You almost have the platform to yourself, since most people will not want to pay the higher price. For "view fetishists" like myself it is just awesome to be out on the open platform at 300 meters above the ground. I had to sign a special paper though before going up, waving any legal claims in case I jumped!
The Observation Deck is nice too, but you will view through the coloured glass and with the beams blocking some of your views. The shops are also located on this floor at 276 meters above the ground.
It's a nice experience and I am looking forward to doing it again.