The only thing I can say is be careful of PTFS/LibLime as a vendor. 
There are other vendors that provide Koha support in the US, however. 
http://bibwild.wordpress.com/2011/09/20/koha-support-or-hosting-options/

On 1/12/2012 1:19 PM, [log in to unmask] wrote:
> Hello all,
>
> I'm curious to know of this lists current thoughts on Koha as an ILS. Where
> would you rank it among the various options, open source and vendor?
>
> Cheers,
>
> Tod
>
> PS: If this has been addressed recently and I just happened to miss it in
> the archives: my apologies.
>