The answer would have to be: Employable as what?
If you mean as a Flying Instructor, then they would both now require a CPL and an additional FI course. This was a long established route for decades for aspiring pilots to work their way up from PPL to CPL. Since the harmonisation of licencing within the JAR member states, working for remuneration as an FI now requires a CPL. In the UK the requirement for the issue of a (non-approved) CPL fell from 700 hours to around 250! As flying instruction broadly falls within the "aerial work" category, that properly reflects the purpose of the modern basic CPL. Although many of these "aerial work" jobs seem much harder to come by, it is still a route for the modern day "self improver".
Spending £40K on hour building is likely to result in a basic CPL/IR and around 400 additional hours (if you are lucky!) A basic CPL/IR and around 650 hours total time isn't likely to open too many doors.
Airline vacancies on to their cadet schemes usually take full time integrated graduates with 200 hours (less on an MPL course) through to advanced training, leading on to a placement with the partner airline. The placement period is usually around 8 months, during which time the cadet is likely to acquire around 500 hours on a modern jet transport or a large regional turboprop. Depending on the partner airlines requirements at the time, it is planned that, subject to satisfactory progression, employment as an F/O will dovetail from the placement.
Many of the first tier airline operators utilize cadet schemes on this basis. It is highly competitive, but nevertheless a fast track route into first tier commercial airlines for many that do successfully embark on this route. The selective, monitored and mentored nature of these programmes results in a fairly low failure rate. Progression to advanced training (the airline part) can be delayed by the partner airlines own intake requirements at any given point in time.
Beyond the cadet schemes, there are few opportunities for low hour pilot employment at this level. The 650 hour CPL/IR is going to be looking at amassing around 1500-2000 hours more experience via "stepping stone" jobs whereby that total experience becomes meaningful, before they reach the next traditional airline employment plateau. With a CPL now requiring roughly one third of the hourly requirement it did 15 years ago, there are exponentially a vastly increased number of aspirants chasing far fewer of what have traditionally been regarded as those "stepping stone" jobs.
In part, it is a case of knowing what you want, where you want to be, and then researching how you are going to get there. That done, the reality is then tempered by what you can afford, your own ability and determination, and of course luck! These three factors alone, will by their very nature provide much of the initial screening.
Airlines with cadet programmes are invariably looking for those candidates who are going to succeed on what is definitely going to be an intensive and very steep learning curve. Training resources are too valuable and scarce to be wasted on anything else. Of course this is why the partner training schools are selected so that this risk is minimized. If this is the route that somebody elects to embark on, the choices are fairly obvious, if no less difficult.
Your 650 hour aspirant isn't going to qualify for most of these programmes. For them, it is largely a case of following the traditional pathways up through the career mountain. Those pathways haven't changed a great deal. However the requirement for the basic licence has reduced significantly, and consequently there are now far, far more people chasing the opportunities that exist at this level. Obvious things such as the global economic downturn have had a marked negative impact on the numbers of those opportunities, and a more subtle shift away from many of the "stepping stone" type opportunities, has also had a marked effect.
That is why I gave the answer as "employable as what?"
There are many careers and not every pathway is necessarily the best use of time or resource, depending on the goal. There are the hard realities of life that often have to dictate the pathway whatever the goal.
I have said it before, but will do so again.
If I were to offer to pay for one course of training for somebody to complete their CPL/IR, which of these three choices (in order) would they pick?
1) Full time integrated cadet programme course at a major FTO.
2) Full time integrated CPL/IR course at a major FTO.
3) Modular course (anywhere) at their leisure.
It is not particularly difficult, and for the airlines with cadet programmes it is not difficult at all.