Help me choose my first spindle

[Desertboy]

Hi building a machine with 1/3 sheet of ply build area out of t slot extrusion with 25mm supported rail on 1 axis, hiwin on the other and Z will be 25mm smooth rod and 20mm ballscrew. Nema 23 powered.

A lot of what I will do is cutting/milling parts from mdf or aluminium to vac form from. Normally it will be MDF but occasionally Aluminium depending on the desired life span of the mold.

I need a spindle obviously but bit confused on what to buy? I want to cut ply, mdf & aluminium at a decent rate and the spindle will be worked 20-30 hours a week. I need something to get me working now and once I've done a couple of jobs for a customer I can afford to get a decent one from Zapp and keep the Chinese one as a spare.

1. I have no idea what sort of power I want, is it a case of more power quicker cutting?
2. From what I read on here it wants to be water cooled and that I should use my own water pump (I have loads), so I will go with water cooled this is 0 hassle to me.
3. Speed control, not sure what a VFD is some kind of power inverter I assume that performs PWM but what's the difference between a VFD and a spindle that supports PWM through Mach 3 (With appropriate circuitry)?
4. Collet size?

I was eyeing up this one
http://www.ebay.co.uk/itm/2-2KW-WATE...8AAOSw-W5Us1mz

The 4 german bearing thing most of they claim how true is it?

I'm guessing it's pot luck on quality.

My friend gave me a brand new router to fit but when he turned up with it I burst out laughing as it's one of these lol

https://www.ebay.co.uk/p/?iid=232188...&crdt=0&chn=ps

Thanks