I have the Macallister one,
@petermillard has reviewed the Titan which was the precursor to it and has a Festool v cheap tool comparison with it.
I really hate the fact it doesn't have soft start. It's a real jolt through the hand when you start it and I feel the need to have the extra focus when the saw is close to the end of the rail.
It came with a 24T blade and when I wanted to change it to a 48T, the hex bolt was very firmly attached and it took me ages to get it off.
I dislike the fact it comes with 2 x 700 rails. A 700 rail really has very few uses by itself.
It obviously doesn't come with a plastic case so it just sits in the box it came in which is now rather tatty.
I haven't investigated yet but I think the depth adjustment is out by about 2mm at the moment... as I say need to check it.
So basically I bought a cheap saw and got a cheap saw. Everything they've done to lower the price - no soft start, cheap blade, no carry case, small rails, cheaper design (blade change, depth adjustment), no clamps I have discovered and found annoying.
As a result, I've bought a new blade (£20), a set of clamps (£25) and realistically would want a new rail (£75-£100), so the initial £100 investment turns out to be closer to £250 if you add those extras.
Having said that, I believe there are some cheaper saws which do come with soft start, longer rails and clamps out of the box. (Lidl, Triton?)
Anyway, when I finally get my shed/workshop, I'm going to buy a TS55. It should last a lifetime with hobby use and with MFT and everything else, will be hugely versatile and forgo the need for a table saw in a small space and I also won't have to put up with everything I don't like about the Macallister.