Is subscription licensing a good deal for clients?

TAS has sold Payroll on a subscription-only basis for several years.This concept was extended a few years ago to the Zebra bookkeeping product. In effect, TAS introduced a type of SaaS (Software as a Service) model, something few of the other on-premise software players had done.

With the launch of the First range last year, replacing TAS Books 1 and Zebra, TAS is now offering customers the option of buying FirstBooks in two ways:
•    The traditional perpetual licence with optional Cover (or Cover Extra) for on-going support (and enhancements), or
•    Subscription package - a licence rental including full support and enhancements. If you stop paying your subscription, the software becomes read-only.

What is the general feeling about the subscription model, which TAS is pioneering and which cuts across the rest of the Sage empire and the wider industry?

Proponents of SaaS tell us that a significant benefit of this approach is that the software becomes a P&L expense item, removing the need to pay upfront for a licence. Is this as good a deal for clients as they would have us believe?