this issue of things looking the same doesn't always indicate anything.
I used to race karts - those of you who have met me will immediately realise that I have the perfect physique for kart racing ahem.
We used to use a pair of Honda GX160 industrial engines on the karts.
Out of the box these are the 5.5hp four strokes governed to 3000rpm and typically cost, from memory, c£300 with a governor on they will run forever. Everyone takes the governor off and puts thin oil in instead of the treacle normally used and immediately they rev to 5000rpm+. They still have a good life expectancy of upto 40 hours before you really need to rebuild them - so long as you don't over rev them - easily done, then they last a matter of seconds

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Still look just like a standard GX160.
You could also buy a race tuned engine for c£800 each. Looks just like a standard engine except it now has a sticker from the tuner on it it will now probably develop 6.5hp and rev to 5500rpm really needs a full rebuild after 10 - 20 hours max (to a much higher spec with new rings, valves, guides, valve springs, bearings all the way through).
You could also buy a chinese copy of the Honda. Looks just like the real thing only they cost under £200. Remove the governor and away you go. Would rev to 5000rpm+. Life expectancy before something lets go in a big way - could be a matter of minutes or it could run for 40 hours. There was no way of telling!
It all came down to the quality of the components inside. The people supplying race tuned engines would buy maybe 50 engines from Honda and then strip them all down and start measuring up the internal components and matching a well balanced crank with an accurately sized piston etc - the whole engine would be built from a carefully selected pile of parts. All of the bits left over would be put together and flogged on ebay. With a governor on they would still run for a loooong time.
Because its all down to the internals, at a lot of race meetings the winner and a couple of random karts would have their engines stripped and inspected to make sure there were no trick parts inside.
This is surely pretty much what is going on with just about all of the heat presses on the market. You can buy a mug press on ebay for £40 and it looks just like one from Listawood that costs £225 plus vat. They may well be the same chassis, but its all down to the internals. You don't often hear anyone say that their Listawood Genie is playing up - leaving marks in the pattern of the element, being wildly hot at one end and cold at the other. Timer not being consistent. You all know the score I don't need to labour the point!
Every now and then a Honda engine drops off the production line where by chance all of the essential parts inside are spot on tolerance wise and make for an excellent race engine and the owner of said engine will tell you that you need not waste money on tuning and that a standard production engine is just as good. When you make 100,000s of these you have to get it right every now and then.
Just a question of - are you feeling lucky, well are yer?
And yes its a slow day at the office, sitting here waiting for a contractor to turn up so I can then go and get some lunch

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Arthur