Here are a couple of my best and worst parts of the tool.
First, it is a great tool for speeding up the process of doing loose tenons but not a substitute as others have said for when hand done is required. That said I use my DF 500 a lot and I have a small custom furniture making studio.
I like the versatility when it comes to using it in both the horizontal and vertical configurations as well as clamping small pieces directly to the fence plate and just mortising in place in the vertical position.
Tool quality is high and nothing too flimsy but not the lightest weight either. Ergonomics is not great though and the fact the barrel grip is basically non-existent is strange unlike the Mafell. The rear grill vent, the plug and your hand isn't the greatest place to plunge from but it gives you the most control. Being up near the dust shroud means one's knuckles get in the way of a deep plunge.
The machine is very accurate which is what counts but as I alluded to before aside from oiling the rails there isn't much maintenance and tune ups to do. I do recommend the extended manual document not published by Festool. Their manual is not helpful.
A few other issues about repairs. All of us know here that Festool does full rebuilds on most issues so if you think they are just going to fix the one issue and not look at the whole thing then prepare yourself because I sent my DF 500 in for replacing one of the power connector pins which had broken off and they found the "pot" for the pendulum needed replacement. The repair went from being around $100 to closer to $300.
Issues then are no LED light for better sighting; no foot on back-end to prevent tool from spinning out on tabletop with the hose connected; poor ergonomics with no rubber grip or properly shaped barrel; lack of fine adjustment on stops other than plastic cams or making your own for the rails; power switch is often too cumbersome; and would prefer aluminum parts as far as accessories but this is the case for nearly all Festool accessory items.
In all it is a great tool but to get the most out of it you will need to fashion from time to time some jigs. In fact I have had some jig design ideas for years which would be great for the Domino. The main one is when plunging not on an edge and so there are many times when referencing off an edge isn't happening. And although there are many after market accessories for doing just that there aren't to my knowledge ones for working somewhere else on the board and in particular on pieces that are not shelving etc. But for smaller more furniture like pieces.
Hope this helps.
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