Southside is spot on. Our T42s have been a standing joke in the RN for at least 10 years. Tired hulls, obsolete un-reliable equipment, a primary weapons system that can't cope with many of the modern threats we see today and main engines that smoke like Buncefield Oil Dept.
By contrast when its gone through first of class trials and associated pain and delays that entails will be a first rate platform which can be significantly enhanced. The same will apply to CVF compared to CVS but on a much larger scale. Lets just hope nothing happens until this slow process has finished.