I purchased 2 Mol d'Art 6 Kg. melters 3 years ago. I was just starting out so I researched all of my options. I chose the Mol d'Art melters for several reasons. The primary reason was that they are silent! This might not seem like an issue but if you are a lover of quiet like me - the churning of a tempering machine running all day long would wear thin. With a Mol d'Art melter, you do the stirring and you are in control regarding the temper - no beeping with this machine. That was the second reason I chose this machine - so that I would HAVE to learn to master tempering. At first, the art of tempering can be daunting. I remember being very stressed about it. It didn't take long to get comfortable with it and now after many years of tempering by hand, I could do it in my sleep and I can keep the viscosity of the chocolate where I want it. This skill is invaluable. Not only do you learn to temper in your Mol d'Art, but the skill transfers to tempering in a bowl or tabling. The end result is you understand what the chocolate is doing. If you're wanting to move on to a wheel machine in the future - you will need this skill.
Another reason I liked the Mol d'Art Melter over a tabletop tempering machine is the ease of use and clean-up. There is no interference when dumping your molds, there is no chocolate clumping up in corners, and clean up is a breeze. The Mol d'Art melters come with European sized restaurant pans. I highly recommend purchasing extra pans when ordering your melter. I purchased 2 melters (1 for dark and 1 for milk) and 2 extra pans (total of 4). When I went to Europe last year I purchased several more pans and lids at a restaurant supply house in Paris. This way I can keep several chocolates stored directly in the pans. So easy. Another thing you can do is buy 2 smaller pans to fit in your melter so you can have 2 working chocolates in 1 melter. This is great for small amounts of chocolate. It's hard to keep a small amount of chocolate in temper if it is spread out over the bottom of your pan. But if it's puddled up in a smaller pan, it will be much easier to keep in temper. These Mol d'Art melters are very versatile!
What I do is melt my chocolate overnight at 45 Celcius. The next day I turn my melter off and remove the pan to my stainless steel table. The only reason you need to take the pan out is to make the tempering process faster. You can keep the pan in the melter if you'd like. By removing the pan, I need to add less seed. The reason this can be a good thing is to keep the viscosity of your chocolate more fluid. I add seed and stir it in. I then do other things and stir it every few minutes just a little. If you want to stir more at this point it won't hurt a thing. Add more seed as needed. The lower the temp. gets, the less seed you add. Wait until the seed is melted out before adding more. When the temperature reaches 34 C, I give it my full attention. At this point, you don't want to add a lot of seed. Add just a small handful and stir. Stirring is key at this point to develop beta crystals. Remember tempering means you are developing beta crystals so you can't just let it cool without any seed and/or agitation (the 3 important factors when tempering are time, temperature and movement). When seeding you don't have to worry about doing much stirring when the chocolate is hotter than 34C. The beta crystals melt out above that temp. so adding seed above that temp. is essentially just to cool it down. In total, because I remove the pans to a table, I use approx. 10% seed.
You will get to know the chocolate you use. Dark is easiest to temper as it doesn't have milk fat in it. I use 2 different milk chocolates and 1 is very easy to temper and the other is fussy. It needs to be taken to a lower temperature and stirred more. It has a higher milk fat content than the easy one. To check your temper, dip a small piece of parchment paper or the tip of a knife in the chocolate. It should set up within 3 - 5 minutes. Take a look at it - it should look smooth with a nice gloss. If it's streaky, you don't have a good temper.
Unfortunately, the chocolate will continue to get thicker the longer it is held in temper in the Mol d'Art. Use a heat gun and play with the temp. gauge as needed. If you have a larger melter it will keep the temper better. You will find that tempered chocolate in a wheel tempering machine will continue to thicken as well - 'tis the nature of the beast! However it will do so to a lesser degree as it is being 'stirred' continuously and has a much larger volume of chocolate. I turn up the heat on my Mol d'Art if it starts to thicken. I play with the temperature gauge constantly. At approx. 1 hour after I start dipping I start to turn up the dial slightly. The timing is arbitrary - I start to turn it up when I notice it starting to overcrystallize. Don't wait until it's as thick as peanut butter. It's amazing how a slight increase in temp. will keep the crystals under control and keep the viscosity constant. I do periodic temper tests to make sure all is well. As long as the temp. stays under 34C I don't worry about it.
Another tip - make sure you set your working temp. high enough to combat over-crystallization. Because smaller amounts of chocolate over-crystallize faster than larger amounts of chocolate, if I had to do it over again I would buy bigger melters - the 12 kg. But that being said, working with the small melters has given me great experience with the challenges of chocolate! Would I buy Mol d'Art melters again? Absolutely, I love them!