Bruce,

>>So, my conclusion is that $ works faster than at() (at least, if I haven't index). I'm going to change my code appropriately.
>
>Sounds good. I'm not surprised, I think AT() is slightly more complex than $.

Yes, so am I. I even can explain, why. So, today I made few additional changes in my code for best optimization. For example, I made another test, comparing what works faster:
INLIST(town,'NEWT') or town='NEWT'. Guess what? :))