Which software package would you recommend for ASHRAE 90.1 modelling?

At the moment I'm thinking:

- IES: more user friendly and likely to be quicker especially
with complex geometries, but expensive (we already use IES but would
have to pay for the ASHRAE 90.1 navigator and related modules and
training, support)

- EQUEST - less automated and less suited to complex geometries
but cheaper and maybe designed more for ASHRAE modelling, less support
(but maybe more support from other users as software is widely used),
based on 'British' units (we are in UK so this means we generally have
to convert units)

- Tas - slow and clunky but gets there in the end, bit of a
non-runner in the long term for ASHRAE as you have to build all the
buildings manually, unless they actually release the long-promised
ASHRAE plug in

Thanks,

Dr Claire Das Bhaumik