I managed to persevere on FFX and get some results but only my some trial and error So far Screwfix is the only site that shows things like cut-depth on the search results instead of having to open every tool separately to check. I think they'll get my business
The plus point of Screwfix and Toolstation is that you can buy something and return it easily with no hassle - the minus point is that it will generally cost you more (at least for power tools). SFX also shave the spec on some tools, so that a particular model on the open market might come with, say, a laser as standard, whereas the "same" model on SFX might have had that feature deleted, but of course there will be no mention of that on the site. So caveat emptor!
No. There are a lot of 110 volt tools advertised, probably because the trade market for this type of tool is a lot bigger than the DIY market and site tools are supposed to be 110 volt on safety grounds. This is not really an issue for a DIYer - you aren't likely to have someone cut through your cable by accident, or to have your extension cables trailed through puddles or to (even voluntarily) work outside in the rain - although if you do work outdoors with any corded tool an RCD plug is always a good idea.
110 volt models are almost always available in 230 volt, but the other way round isn't always the case. If your chosen tool is available as 110 volt and 230 volt it indicates a trade quality tool
Yea it's a bit like TV's, you buy a TV from John Lewis it will have a model number and spec, you buy the 'same' TV from Tesco fr a tiny bit less and there'll be a very subtle suffix or number slightly different with a downgraded spec.
The 110 volt we use on site is actually "centre-tapped 110 volt" - so if you measure each leg to earth it reads +55 volt on one leg and on the otrher it will read -55v (which gives a difference of 110 volts). The principle is that if you ever grab one live wire by accident you only get a 55 volt belt off it which is a lot less likely to kill you than a 230 volt shock...
Not that I'm keen on trying it out in person
A couple of other things about mitre saws - it is safer and physically less stressful to use them on a bench or on top of trestles (I have screwed one onto an old flush door supported on piles on Thermalite blocks before now), and without exception they generate a lot of dust, even when attached to a vacuum cleaner, Even the very best of them, the Festool Kapex, is really only so-so in this respect, so mask wearing when using them is advisable