Does anyone know a comparison (or by experience can describe one) for Custom forms Modules?
Software like H20, Dynamic forms, form Master, Enterprise forms, XMOD.

Thank you!

From your list I've used H20, Enterprise forms, and XModPro (not exactly XMod but probably the way forward there).

H20 is probably the easiest of these to use with little coding and good documentation. Though I do worry about some of the security issues with OnyakTech modules.

Enterprise forms (not the current version anyway) is good with getting workflow in place but I did find it a painful tool to work with as it needs to have a bunch of settings changed to edit the form, and then changed back again to run it.  Also adds crazy numbers of tables to the database.

XModPro is overall probably the best here that will give you more flexibility and control... though you will have to code a bit. Documentation and support is quite good so it's not a big jump from html and pain-free.

Another which is now my favourite well above any of these is OpenWebStudio. A bit of a learning curve, but for forms this is rather minimal and there's some samples, videos and a quickbuilder to get you going quick enough.  It's the fastest to use, friendliest and most organised to use and the most powerful and flexible... plus it's free!

Depending on your needs, you might also consider feedback designer and formmaster. I use both for my endusers: feedback designer is extremely easy to use and formmaster is both easy and powerful.

Peter