Neil Mc,
It all comes down to budget and perceived value for money.
Mechanically, most of the mini-lathe family will be similar, with small differences in assembly QC.
Amadeal have a 100mm flange as standard for lathe chuck, although ARC, and engineers at SIEG do not agree with the idea, based on load over length of headstock casting support, combined with load on electronics. This is a matter of opinion which can and has been debated over time. This is down to customer choice. Wherever 80mm chucks are fitted, 100mm chucks and backplates are available, only because some customers want them, but not something which we recommend.
The cheapest should be brushed motor versions of mini-lathe. At the cheapest level, there will be no overload protection on board. So, probability of the control board/ motor getting damaged increase under an overload situation (similar to C2)… especially for a beginner. The higher level brushed motor versions (C3) will have overload protection on the control board. In all brushed versions, the fai lsafe is normally the high/low plastic gears. Some people prefer to change them to metal gears, increasing the probability of damaging the control board/motor under an overload event.
Then come the brushless motor family which are now a days sold in two ways…:
A.: gear drive – with high low gears and a 'small' brushless motor – similar to the one in your opening link and which is probably the same as the Warco brushless offering… sold as Superior or Super respectively. The power stated is probably/possible 'input power', 'open to question' as the motor appears to be too small in physical size to be output wattage, because if it was output, gears would quickly break!!. These are not made or supplied by SIEG. See following threads for further understanding:
Warco Super mini lathe (probably same as Chesters Superior lathe) See the size of the motor. It seems to look smaller than what a 500W brushless motor of this type should look like. Also read this brushless motor thread.
B: Belt Drive – SIEG models SC2 and SC3. These are 500W output. The physical size of this brushless motor is 130mm (overall length) or 100mm motor length x 80mm x 80mm. See picture here . There is no hi/low gear to break in these models. The torque control comes from programing on the control board, rather than mechanical gear drive. Till date, competitors of SIEG are unable to achive this with their brushless motor/control board setup.
Strictly speaking, based on the above, the SC2 and SC3 should be the most expensive.
Competitor marketing is selective in use of words 'Super'… 'Superior'… other; and in certain ebay cases, the machines are made to 'look bigger'… often plugged by certain members on here, but on close examination, it is just a standard mini-lathe made to look bigger with addition of sheet metal, and looking at the electrical content soon proves that one is dealing with a product which could be considered to be even cheaper than a low specked mini-lathe.
Most manufacturers are guilty of failing to specify what they mean by power, be it for input or output. Certain distributors also exaggerate the power stated, but can still justify this as some form of 'input' power'. SIEG always states output power which is lower than input power. However, we know that some companies who buy from SIEG want them to state their own version of the meaning of power, as it is their own company brand interpretation of power.
Unfortunately, presentation of such facts does come across as a 'sour grapes' issue, leaving the potential buyer to make up his or her own decision, which can still prove to be good, bad or ugly.
Having said all of the above, based only on price, the Amadeal second package does appear to be good value for money, for what it is.
Ketan at ARC.