First of all, welcome to CPF!!! I hope you enjoy your time here. Second, I've never bought one of the ZL frosted lens versions, so I couldn't honestly answer you on that question. I will say, however, that the SC700d is already reasonably floody, so I'm not sure you'd really need to get the F version, and, more importantly, the filter swatch books that you can purchase for less than $10 (specifically the Lee Filters Designer Pack),contain not only a large variety of colored filters, but also contain a large variety of diffusion filters as well.
This has the added bonus of first, letting you purchase the regular unfrosted version of the light to see if you like that, and then if you feel you need more diffusion, it's a simple matter to go through the filter pack and pick exactly the level of diffusion you prefer.
The only downside to this, as far as I'm concerned, is that with the ZL current lineup, the filters must be attached to the front of the lens, usually with a small square of double sided tape, and although I've never had a problem with this method, it's something to consider.