Warco WM18 or WM16B

[hedeon]

Hi.

I am a newbie in to the world of CNC, but have been dealing with self-build 3D printers for some time, so some concepts are similar.

I am trying to pick a milling machine as a base for future conversion to CNC. I am stuck between 3 machines, Sieg SX2.7, Warco WM16B, and WM18, but would like to discuss 2 of them here.
WM18 is only a little bit pricier than WM16B (£1450 vs £1250) but is a bigger machine substantially. Weight alone is 220kg vs 125 kg and much wider ways. Just from specs WM18 looks like a much better machine, however, there is one downside - spindle speed. WM18 spins 2250rpm vs 3000rpm in WM16B. I know that this is important factor for CNC. How much? Can you guys give me your thoughts about it? I will be machining mainly in aluminum but would like to try some harder materials as well. This is for hobby use, rather small parts for now.

P.S. I would also consider GH18 but this gets only max 1450rpm... Is it worth concidering?