I shall reply as Web Developer who works (has worked) with CWP and IWP/WD (even other databases & web apps). I can do anything (well within reason) with CWP, because I have the skill set. My client(s) who has the desire to make changes & additions, does not have that 'web' skill set for CWP. But client can make some really good WD layouts & scripts (based on my tutoring and templates) that don't need my help (most of the time). The difference is paying me to do the work and do it when it's needed (usually yesterday) if there is a change/addition/need.
But there's an expense (me) with CWP. Pay for my skills/time (I'm good, so not cheap); the extra hardware (possibly), syncing solutions (possibly), plug-ins (possibly), and more? I may not be available when needed. Weigh all that against the cost of the licensing for WD.
Completely second what beverly states.
While you can eliminate the licensing cost with CWP you will incur other costs. Either in learning curve / time if you want to become proficient with it yourself or in development cost if you outsource it.
The first choice you'll want to make is the technology stack you want to use (and invest in). Very often people default to PHP since that is supported by FM. But there are many others just as suitable. .NET, Ruby. JS,...
If you are going to go to the trouble of becoming proficient then give this technology choice some careful consideration because ideally you may want to pick something that is going to serve you in your market space / client space for non-FM things too.
I will also add: IF you need to do something that is NOT possible in WD, but can be done with CWP, then that is your deciding factor (and is for many of my web clients). There are limits, we know it. Limits in FMP, in WD, even in CWP. Integration with SQL (or other db) may be required to do what is needed. But IF it can be done with WD, then reconsider 'the cost'.
It is WD ready. I have one loads of WD solutions but they have been for corporates. Licensing is not an issue. This project is on spec. A mobile app. FM Go is just not an option due to ridiculous costs. Neither would the bundle solution work (obviously). Th only thing to get this ff the ground is CWP and I know nothing about it.
Are you well versed in CWP?
Points well taken and I do agree. I'm not interested in PHP or any of that stuff if truth be known. Perhaps we can find a person that is and wants to do this on spec. The solution is ready to go and works well.