Agreed - thanks for the answers everyone.
Adding sales/yield management/work que management/crm and ipad remote access for reps, etc - and the choice is not so clear in systems (and pricing moves to whole different league!). Currently looking at RadioTraffic, SDS & WO, but may yet come back to Natural Log to contain costs.
Chris, Natural Log have a fully working downloadable version with sample DB on their web site. Few minute install. Easy. Think I'd be tempted to consider it over VT as well.