Lionel switcher

Yes all of the recent Lionel models you mentioned have the same drive system.

It's NOT a bad system; it's actually more like what has been used (and is still being used) for SCALE MODELS in O and all smaller scales.  The two vertical motors that are mounted on and swivel with the truck is a toy train thing.  That design was originally necessitated by the need to negotiate insanely sharp curves.  It lives on in modern times because it's cheap to build, and it leaves plenty of room in the shell for the big stack of electronic boards that most 3-railers can't seem to live without.

There are a LOT of disadvantages to the dual vertical-motored drive and I have posted comparisons before (search my posts.)  One legitimate advantage that vertical motors might have is servicability.  It's usually easier to remove the motors and trucks if necessary.  But, unless you're talking about one of the recent Legacy LionDrive diesels, if a motor or gear does eventually fail, you'll need an exact replacement (because not all worm gears are alike, and the worm can't easily be removed or installed on another motor shaft.)

The one issue which seems to be reported about these switchers, is excess side-to-side play in the wheels / axles which affects the mesh of the spur gear train on the side of the truck.  If mine had that problem, the first thing I would do is to order two new trucks from Lionel (in hopes of receiving ones with better tolerances.)  And if the best two trucks out of the four still had excess slop, then I would try shimming the axles with thin nylon washers (bread bag clips) or e-clips.

All in all, a minor risk considering that the recent Lionel EMD switchers are among the smoothest, slowest-running locos ever released for 3-rail O gauge.  If you run your trains "hands on" and want a switcher to use for realistic switching, these new Lionels are the ones to get.  My $.02.

Thanks TedS will check out your posts on this subject. Did a search for Lionel switchers but got everything but the SW1, SW2 and NW2 switchers

The early 2000s Alco switchers (S2, S4, etc.) were the first Lionels to have a single motor with drive shafts to the trucks.  They were a good start, but the design was refined perhaps 6 or 7 years ago?  The orientation of the motor was changed, and IMO performance improved.  I think all of the switchers produced with the new design were ElectroMotive Division (EMD) models such as SW9, SW1200, in addition to the ones you mentioned.  Lionel hasn't used the shaft drive in a road diesel (although all of Sunset / 3rd Rail's diesels use a centrally-mounted single motor and drive shafts.)

If you want to know more about why I (and some other discerning Forumites) prefer this design to the twin vertical-motor setup, search the Forum for phrases like "China drive."

Ultimately it's your decision.  How do you run your trains?  Do you actively switch, or just turn it on and let it run?  How fast?  How many cars?  How sharp are your curves?, etc.  All of these factors should influence your choice.