Hi scoffey, and welcome to Outdoorking. The belt-drive Scott Bonnars (principally the 430 and 590) are less traditional than the more conventional reel mowers such as the 33 and 45. It does seem that both collectors and serious mower operators prefer the 45, in particular, but the belt drives have a couple of specific advantages, such as a rear catcher that makes it easier to cut around bushes etc. Generally it depends whether you are collecting or mowing, and whether what you are mowing is long clean runs or working around obstacles.
Because there is more demand, more literature, and more collector enthusiasm, for the 45 in my opinion it is probably more suitable for restoration than a 590. On the other hand if you just want a mower to use, in a small and complex garden, the 590 does seem to have advantages in smoothness, flexibility, and simplicity. Perhaps you should give some thought to what motivates you in this purchase: collecting, or just having a fairly simple lawnmower.
Anyway, you're just about sure to get a variety of opinions on the subject here on Outdoorking.
