Oh my god, so I bought the Makita 1.25 HP router, and the Dewalt 611 mount with some shims, and holy crap. This is singlehandedly the best upgrade possible for the x-carve. Honestly, Inventables needs to can the 24v spindle, it detracts from the x-carves true ability as a desktop HSM and woodcutting beast. I just finished a test design at 10,000 RPM, at 75 IPM!!! and that was being conservative! Full depth too! This router just ate the birch like it wasn’t even there. Completely no chatter, no runout, just beautiful milling. To anyone still using thee 300W pile-o-crap, upgrade. Upgrade immediately, to a trim router, or a vfd. It is magic. I cannot wait to see this thing eat aluminium and plex. The Makita router is amazing too, 10,000 RPM all the way to 30,000, and its quieter than the stock spindle at low speeds! It feels, and performs like a quality tool. so well built and just wow. Can you tell I’m very happy? And props to Inventables to shipping so fast! You are awesome!
First test, full depth, in this case 0.06 at 10,000 RPM, 75 IPM!! ate it like butter in 5 minutes. Took 30+ mins on stock spindle, at 20 IPM, and only 0.02 depth.
Look at this beautiful machine. Does blow dust like a cyclone, but I will be making a dust shoe for it anyway.
And obligatory side by side. I mean really, once you get the stock spindle out of the mount its just a pathetic little pencil sharpener motor. If you want to do things right, or cut mill aluminium, or plex, you need to upgrade. The stock spindle just cant go fast enough for acrylic, and doesn’t have the HP for depth.
Between the new spindle, and the x-axis steel spar mod, I have so much more confidence in the x-carve. The x-carve was awesome even without the spar or a new spindle, but you really could not push it too hard, or you would break bits, and get chatter. The steel spar completely eliminated frame flex, not that there was much on the 500, But it got rid of the tiny amount, and rigidity is super important. Now with this router, I feel like if I see something I want to cut, I say, yep, I can cut that. instead of, maybe I could cut that, but it would take forever since its so thick… 
Next step is NEMA 23 steppers. but for now the 17’s are okay. I haven’t run into their limitations yet. Gotta love Inventables for having this kick ■■■ community as well, We are making the best desktop mill ever 