My first ride on a SMRT DD (copied from another thread, so don't
be susprised when you see double!): 
Took SMB3503G on 972. When I boarded at Blk 270, the BC had to
remind the passengers to not stand upstairs and had to go down...
The aircon was good, though quite weak at the front before the exit
doors. The bus accleration sound seems like a KUB doing a kickdown,
but shifts gears at the same times as a ZF Volvo B9TL Wright. The
engine sounds like a whistling unit, but one can tell when the
gearbox changes gears by the unique whitsling sounds that come with
the gearshifts.
The lower deck is okay, but I rather have the seats at the rear
half facing sideways like the Volvo B9TLs, instead of transverse
seating. Unfortunately, I couldn't go the upper deck during the
trip, so I will need to take this bus again to try out seating on
the upper deck. But overall, the bus is quite smooth and
comfortable.
It has different features from the regular buses you find, such as
different 'BUS STOPPING' bells, factory-fitted buzzers (BUS
STOPPING and DOOR CLOSING) and tree guards at the upper deck front
window. Ventura doors are quite good at opening and closing quietly
and properly, though the rear doors take a long time to close (the
exit door buzzer turns on even before the doors close and after!)
But I believe that we will get used to these differences when more
units come. Not bad, SMRT.
For the Ventura doors, the Door Closing chime sounds first as a
warning before the doors close, just like a train... This
configuration is exactly the same as all HK's E500s...