Well... the cases aren't quite done (no liner/inner coatings/paint) but I've done a road test... about 100 miles of road test actually... Even without the cross-seat straps (which I decided were unnecessary) and without lids (which I figured would make for a better worst-case test) the boxes are fine at any speed I'd care to admit to.
The lids right now are black vinyl... these will be the "soft" lids for when I'm carrying bulkier items or things (like fishing rods?) that need to stick up through the top. The hard lids will unclip so these can be used. Truth be told I scrapped my original hard lid design when I looked at the Jesse Bag site again... figured I would make some box lids that could store some MSR fuel bottles. Why not?
Plus the black vinyl adds a certain je ne sais quoi.
Side View/close-up: (click for larger)
Rear View: (click for larger)
Front View: (click for larger)
Yeah, I went a little crazy with the bolts on the rear brace... I was going to rivet it at first so I spaced the holes fairly closely but then I decided I might want to part the cases from each other without drilling so I used bolts instead...looks a little paranoid but it is strong.
The forward location (compared to standard saddlebags) keeps the CG low and within the "load triangle"... I've loaded 25lbs in each side... (as much as I plan to carry) and I'm rather pleased with how the bike handles with them loaded. Given that this is a 250, and given my weight, I'm not too sad about giving up the rear passenger pegs. I might, if I decide I sometimes need to carry passengers on this bike, make some extensions to move the bags back a bit... but let's face it this is a 250... you want luggage and a passenger you should think of a bigger bike.

Right now they remove with four bolts total.
The angle of the front is perfect... I can bump the heels of my alpinestars on them if I put my tiptoes on the pegs, but otherwise I don't know they are there... what else... the reflectors are stock reflectors off the rear fender moved. The turn signals... turns out they have two modes, "running light" and "turn signal"... when I first hooked them up I hooked up the running light side. I was a little surprised at how dim they were compared to what I remembered... and they were flashing fast which they hadn't when I tested them... but LEDs always flash fast with thermal flasher right? And with them flashing so quickly I figured maybe the dimness was just that they weren't on very long. I've read you need solid state flashers for LED lights...so I went out and bought a solid state flasher. Then I pulled my head out of my ehem and hooked up the other wire... MUCH BETTER.

These lights draw about 8.4 watts when lit in "turn" mode, which is enough to work the thermal flasher... I took the solid state flasher back today and recovered my $9.65.
My cost:
$6.50 for the rear brace aluminum.
$40 (approx) for the box aluminum (I used part of a $90 sheet)
$3.50 (approx) for the stainless steel parts...they were scrap I had lying around so I'm not exactly sure.
$50 (25/ea) for the LED turn signals (from a Pilot truck stop... you could probably get them cheaper online but what about shipping?)
$8 for the connectors that fit the turn signals (again, from truck stop...)
$2 (approx) for all the other hardware, wire, electrical connectors, etc...
$3 (approx) vinyl for the tops... the stuff was $15/yd but I didn't use much.
$5 (approx) velcro.
$10 sales tax paid on materials
$130 (approx) total price.
Of course, what sucks about that is the labor involved... this was the first time I've tried something of this sort (I'm a computer guy by trade)... but for me it is slow fiddly work to come up with something even this quality. I really admire the folks who can take a sheet of aluminum and turn it into *anything they want* and it comes out looking beautiful. In all honesty, these boxes represent about four days work... that's design, prototyping, fitting, fabrication, wiring, everything. I could probably do them in a fraction of the time now that I know what shape they are supposed to be but still they were a lot of work. It's a good thing I'm able to lump this in with "airplane building" as a hobby/craft type time expendature or I'd have to fire myself for inefficiency.
Another view: (Click for larger)
Oh, and, total weight as pictured... anyone care to guess?
They add less than 10lbs to the bike...

7.5lbs without the lids and the lids weigh about 0.5lb/ea actually.
(don't bother clicking.

)
There you have it... the commutin'/tourin' two fiddy one step closer to obsolete.
BTW: Thanks everyone for those kind words which have already been said.

Ride it like you think owning it matters.