captinjohn, every one of these 7x, 8x and 9x have their pluses and minuses. You just have to decide which fits your requirements best. For example, if you need to cut left-handed threads frequently, 7x is a better bet. Neither 8x or 9x come stock with a reverse tumbler gear for the feed screw. OTOH, if you need the extra inches (for gunsmithing say), 9x is obviously the choice. Keep in mind, though, a lathe should really be qualified by the chuck size, not the swing-over-bed. There are a few folks who put a 5" chuck on their 7x - not for the faint of heart IMHO - but they can hold just about any workpiece a 9x with a 5" chuck can. Between centers isn't much of a concern for RC stuff, since most engine work don't involve anything longer than 10".

I ruled out 7x from the start, because of the size issue and the fact that you pretty much have to rebuild the darn thing to get any sort of precision out of it. Between the 8x and 9x is a tougher choice. I went with the 8x because even though the "spec" reads smaller (8x14 vs. 9x20), it is actually substantially beefier than the 9x. The 8x14 weighs more than the 9x20. The ways are induction hardened and physically wider and the prizms larger than the 9x. The 5" 3jaw and a 5" 4jaw I have for it are plenty big enough, though I've been keeping an eye out for 6" or 6-1/4" 6jaw chucks on Ebay. The lead screw on the 9x is of a somewhat small diameter and very fine pitched. Some owners have reported problems with that.

Again, those are just my thoughts. The 7x and 9x are much more popular and so enjoy better aftermarket support. In the end, any of these will be a good starter lathe. I'm already looking ahead at 12x36 and 13x40.[>:]