Mick...here is the story related to Laguna vs. Grizzly on the Revo model and the G0799 and G0800. First here's a pic for you to see the G0800
The Harvey Industries Co. is the maker for the Powermatic line of lathes, and also for Laguna's Revo line and Grizzly's G0800, G0799 and G0835. Of course each lathe is made to specs of the individual vendor, and that accounts for differences in design, features and build. For example, the REVO line has steel bed ways, where the Grizzly has an all cast build. The Revo has the movable pendant feature [nice!] where the Grizzly does not.
That being said, when I did the deep dive into the schematics of the lathes I was considering, which I was actually saving for a Robust American Beauty [super lathe, and I have had turning sessions on one] and I was considering a Oneway 2436 [I have a friend who has one] and of course the Laguna Revo 2436 and the Grizzly G0800.
With the turning I do, which involves some big heavy wood, and wanting what I considered to be a high end lathe that had the power, weight and heavy duty build, I chose the Grizzly G0800. I could have gotten the Robust AB, or any other lathe I wanted, and also had turned on the nearly 1600 lb. Serious SL2542. I wanted the sliding headstock feature, and the heavy duty build, and the Serious did not have the sliding headstock.
As to build, the G0800 has 3 large heavy rated bearings, and all three are bigger than a baseball in diameter, where the Revo 2436 has two bearings which are smaller with less dynamic load rating. That is fine for most folks probably because they likely do not put as heavy wood blanks on their machine. Once in a while are fine, but a steady diet of large wood probably will show up in worn out bearings. It's sort of like having a small pickup vs. a super duty pickup with the heavy frame, powerful engine, and other features that make it ready for heavy duty work.
Another thing was the inverter/motor combo difference. The Laguna Revo uses an older Delta S-1 inverter for their machine, which is on the lower end of the technology that is available, but it has been a good workhorse inverter used on the Powermatic lines and the Lagunas as well. The Grizzly G0800 uses an advanced induction motor with the latest advanced Delta EL-240 inverter, which allows a full 3 hp output vs a 3 hp input only, so the motor power is fully available.
The information from Harvey Industries is the Harvey Turbo-60 lathe [their flagship model] and the G0800 are almost identical, except that the T-60 uses a DC motor because it sells all over the world, and that seems to accommodate the market, but here in the USA, they use the A/C motor inverter combo, as that is what is desired by turners here in America.
The G0800 has a swing away tailstock feature, a bed extension available [I have that on mine] and in stock configuration has 48" between centers for longer spindle turning such as bed posts, etc, and with the bed extension can turn 66" between centers. The extension is configurable to either end of the bed or on the mounting area on front of he massive cast iron bed near the headstock if one wanted to put it there. It has a cone heastock feature like the Revo 2436, and it is heavier. I have never seen any better machining on any lathe from any manufacturer, including the Robust lathe I have turned on and seen up close from vendors at the symposiums I have attended. It is absolutely top grade machining! Fit, finish, and machining are superb!
The G0800 has superb torque at low speeds and is as smooth and powerful as any lathe I've turned on. The warranty is longer on the Robust and its made in the USA, and a longer warranty is also on the Powermatics. I have turned on the PM 3520b numerous times - too many to count- and eleven different lathes to date on that model........ I like the 3520b, but hands down would take the G0800 over it any day of the week! Again PM and the Grizzly G0800, G0799 and G0835 are all made by Harvey Industries Machine Co.
So, there you have the back story on the comparisons, and you can see the G0800 at Grizzly.com if you are so inclined. I post this by way of providing info for interested persons, and to answer your comment above. So many folks don't realize how fine a lathe Grizzly is now providing, and I would encourage others who might be interested to take a serious look for themselves. Only they know what they truly want in a lathe, and how a certain model will fit their needs.
Good luck Mick, with your Revo repairs....I hope it goes well for you!