Hi Astroman,I have a standard EQ6 mount .
They will easily handle a 10"f6 or a 12" f4.5 Newtonian.
They have a 25kg load handling but you have to watch the length of the OTA. 1500mm will be OK .
I have mentioned the following else where but will repeat it here.
They are for the $1500 pretty good but do have a few little things that need dealing with depending on the Quality control of the unit you buy.
Namely PE and back lash .
The quality can vary although it appears to be less of a problem with new units these days.
I have herd that the new SkyScan EQ6 the one with Go-To has addressed some of these problems but at an Aussie cost of $3000-$3300 depending on who is trying to rip ----I mean selling it.
If your on a budget get the EQ6 standard and upgrade later on.
You can get a Sky Scan upgrade or one of the various after market upgrades.
The after market ones are cheaper and can offer things the Sky Scan doesn't.
One of the better after market ones is from a company called
http://www.astromeccanica.it/da1_ENG.htm
http://www.astromeccanica.it/motor.htm
This upgrade with an EQ6 will cost less than a Sky Scan.
The beauty of this unit Go-To is in the motors and gearing.
What it does is to eliminate any back lash and PE of an intermediate gearbox by doing away with it .
The subject of much of the problem with an EQ6 is the intermediate gearbox on the motors..
These upgraded motors also have more torque than the originals and will allow for faster slew speeds.
The Go-to will work stand alone or can be integrated to most star charting programs and even the free ware one called Carte De Ciel.
There easy really easy to fit even for a novice and you will have the original controller and motors to refit incase of the worst case scenario.
Mark