Adam, I always recommend *ANYONE* buying a high end *ANYTHING* does a quick and dirty test. Ring Vendor "X" (Quaife in your case) and see if they have a few potentially commonly needed bits on the shelf, say dog rings, a few random gear ratios, a couple of selector forks and a sequential barrel selector. Bits that are probably unique to that box, and you could need at any time, in a hurry. Throw in a couple of castings, too. If they haven't got them ask how long before they have, and at what cost. If you do the same for any high end car items like dampers, engines, clutches, diffs, blah blah, you can easily weed out the potential nightmare, even boat anchor buys from those that could be repaired without either breaking the budget or waiting 12 months / forever for bits. I apply i to anything over a grand, and the test has saved me a LOT of grief, and caused a lot of amusement. I thank my late father for the tip, he was a canny old *ugger, who used the test on white goods, car bits, electronic gear etcetera.
Tracktive will be amazingly good, as will, to a lesser degree, Hewland, let us know re Quaife

I can guess the results though.