Pre-calculation of loads with Dimmer modules - effective dimming range?

Hi all - planning z-wave module setup for a electrical re-wire in a renovation. Trying to decide between dimmer modules and switch modules in certain switches. But am struggling to understand how dimming range works in practice given the load constraints on dimmer modules.

Let’s assume I am using Fibaro Dimmer 2. Rated 50-200VA (without bypass) or 5-200VA (with bypass). Assume 3-wire wiring at switch. Then are these calculations correct for hypothetical circuits below?

Circuit A: 5x GU10 5W LED spotlights with power factor 0.8 => 30VA draw in total. Assume this would require a bypass module? Consumes 30VA at full power or 5VA at 16% power. Therefore able to dim from 16% brightness to full brightness - pretty much full range?

Circuit B: 1x GU10 5W LED spotlight with power factor 0.8 => 6VA draw. Assume this would require a bypass module? But module would only consume 6VA at full power and therefore even with bypass module in place it would in practice not be dimmable? And in fact it might be better to use a switch module instead?

Circuit C: 5 x 15W B22 LED bulbs (in table lamps) with power factor 0.6 => 125VA draw. Assume would NOT require a bypass module? But without bypass it would only be possible to dim to 40% (50VA)? Could I add a bypass module and dim much further down to 4% (5VA)?

Thanks for all help!

@anon36505037 - do you have any wisdom to provide on this?

Power factor only comes into calculations for AC loads, mostly in industrial environments.
I would only look at wattage and quality of the dimmers and bulbs. Wattage rating for dimmers are given for the load.
I have 60 and 150 watts equivalent from Costco and I can dim them down to 1% with GE and Zooz dimmers. I also tried Ecosmart from Home Depot 100 W equivalent from Costco and they would not go down below like 30%. I use them with On/Off switches (GE Smart switches).
I have neutrals in all boxes and never used any bypass modules.

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Many thanks Robin - that is reassuring. All of my test installation is on a 2-wire setup so I didn’t have this confidence.

Thanks NomadTech - my question is specifically about the Fibaro Dimmer modules which operate behind normal (dumb) switches.

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