I do have experience with all three to a greater or lesser degree. Please take these remarks as subjective as like all people I have my own preferences for tone, versatility etc.
Musicmakers: my favorite among kit makers; the larger harps are pretty easy to put together even if you have no woodworking experience. I prefer the Voyageur most of all although it is heavier than some others at 24 lbs./11kg. Beautifully designed and easily upgraded to concert level by purchasing a solid wood soundboard and making a slight modification to the pillar foot.*
Stoney End: Gary has been making harps for a long time with one standard design, which is lighter than many others. That is because he uses plywood glued to hardwood “L” wood strips for the box sides, rather than solid wood like the Musicmakers and Cambria. Personally I find that more difficult to put together for an amateur woodworker than the other two. Like the Musicmakers he uses a high density laminate board – it too could be replaced with a solid wood board*.
Cambria: Glenn has also been around for a long time and mostly specializes in custom designs; IMO his kits are a sideline. The board is solid wood. I have seen few in person but several people I know have had some difficulty putting them together – inaccurately placed dowel holes being the most common “complaint”. That can be dealt with by using an epoxy resin glue but to my mind that falls more in the line of repair than construction.
*The pillar foot projects through the SB with the standard laminate board. If you replace it with a spruce or other wood board you have to chop that projection off and bolt the foot through the board and string rib, rather than screws from beneath. A solid wood board may be purchased from Betty Truitt (Dragon Whispers) or Rick Kemper (Sligo Harps). Look at what they offer before deciding – Rick offers more options (veneer or no veneer, spruce or cedar, add string rib or not, etc.) but both are excellent, experienced harp makers.
Have fun and best wishes,
Biagio
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