I can hardly believe I’m saying this, but if you really want to take Windows 8 for a spin and get the best possible experience then you should just plan on getting one of the new hybrid tablet/laptop machines that many of the leading PC makers are going to be selling this fall.

That was my conclusion after moderating this week’s ZDNet Great Debate between Jason Perlow and Steven J. Vaughan-Nichols on the issue “Does Windows 8 belong on older PCs?

Here’s what I wrote in my verdict at the end of the debate:

“Because Windows does not have a very good track record on operating system upgrades when it comes to stability and performance and the fact that Windows 8 is adding such a radical new user interface to the desktop, it’s difficult to recommend that any but the most curious technophiles should upgrade their old machines to Windows 8. Instead, try it out on your next laptop, especially if it’s a touch-screen hybrid.”

ZDNet users felt differently. They voted 74% to 26% in favor of putting Windows 8 on older PCs.

However, I think a lot of users who end up installing Windows 8 on their current Windows machines are going to be pretty frustrated. The Modern UI (formerly “Metro UI”) is heavily slanted toward a tablet experience. Using a mouse to navigate the new UI on a desktop feels awkward and confusing. It’s kind of like trying to poke a giant in the foot with a pin in order to get his attention. You quickly realize that you’ve got the wrong tool for the job.

On the other hand, if you’re using Windows 8 on a touch-screen tablet, there are some tasks like setting up a VPN where Windows will kick you into desktop mode and force you to clumsily tap your way through menus that were meant for precise mouse clicks.

This split personality disorder is the biggest problem with Windows 8 and it’s going to lead to a lot of teeth gnashing when it’s first released. I think Microsoft will eventually refine it and get it right, but be prepared to hear lots of complaining for a while.

Ultimately, that’s why I’m going to recommend that those who really want to take advantage of the good stuff in Windows 8 just opt for hybrid. That will allow you to take advantage of the cool Modern UI apps like the built-in travel app, while also staying efficient and fully capable when you have to switch into the traditional Windows desktop to do certain tasks or run legacy apps.

I’ve never been a fan of dual-purpose machines. The failure of Microsoft’s Tablet PC and HP’s TouchSmart devices are evidence that these kinds of machines don’t appeal to most users. But, advances in multi-touch hardware/software and the arrival of thinner, more versatile form factors should make this new fleet of hybrid Windows 8 devices worth giving a shot. At least in the first iteration of Windows 8, it’s clearly going to be the most effective way of dealing with the new Windows.