I have a few different pads. Exped Downmat, Thermarest Trekker and Thermarest Uber lite, and my favourite of them all is my Sea to Summit Comfort plus.
I use the Uberlite for my emergency bivy set up due to its incredible light weight. I've tried the chip bag Thermarest Neo-Airs, but I don't like the noise or the air mattress feel.
The Sea to Summit Comfort Plus insulated is truly an amazing mat for how comfortable it is (I'm a side sleeper). I think the thing I like the best is the dual-layer 696 individual air sprung cells, it doesn't have that air mattress feel, and the two separate layers add a safety layer incase of a puncture. I also love the pump sack inflating system, its the best I've used by far. It's also super warm with R5 insulation.
The only downside is... 35 ounces for the Large mat. I used to bring the lightest gear possible, but as I'm getting older I prefer a better nights sleep than worry about the extra pound or so weight.