Looking to the future---for me

[klaviator]

I think Freeway advice is coming who does not use it on small (but legal) scooter----slow scooter, 4 new Helix and 175,000 miles for me worked on US Freeways and Japanese Toll Roads, 150 Vespa on the Autobahn in Germany----There is always speed differential, even on my Kawasaki Concours or BMW K-75 or BMW R80RT.

Freeway much safer than surface streets in US---at least everybody is going same way!   I like slow lane, too.

The Like 150i is not interstate legal in some states which require over 150cc.  I have ridden mine on I565 in Huntsville for a short distance.  I would not ride it on most interstates.  The Smax on the other hand would handle interstate speeds pretty good but I wouldn't have felt comfortable going a long distance on the interstate on it.

[Kansas kymco]

Different states have different speed limits as well. I-70 in Kansas is 75 mph and people run 85 mph .  I would not want to ride my 150 in that situation.

[Ex-KLR]

I'm 83 and the Like 150i is a great scooter for me.  A couple of 150 mile days were no problem.
I installed a windshield from Amazon and modified some soft bags I had on my KLR 650 to fit the scooter.
I'll take it anywhere but the Interstate.

https://www.amazon.com/Slipstreamer-S-SCOOT66-Universal-Scooter-Windshield/dp/B001EB9WPI/ref=sr_1_7?crid=1Z7OZQ4K05006&dchild=1&keywords=scooter+windshield+150cc&qid=1592257490&sprefix=scooter+windshield%2Caps%2C530&sr=8-7

[klaviator]

Different states have different speed limits as well. I-70 in Kansas is 75 mph and people run 85 mph .  I would not want to ride my 150 in that situation.

I wouldn't have ridden my Smax there either.  Well maybe if the traffic was really light I would.  The thing is that very few people who tour on a 150cc scooter would plan to spend much time on the interstate but sometimes you just have to get on an interstate for a little bit to get places.  You could certainly ride a Like 150i across the country.  People have done it on 50cc bikes.  Personally I'd prefer a bit more speed for a long cross country trip.

[Kansas kymco]

I wouldn't have ridden my Smax there either.  Well maybe if the traffic was really light I would.  The thing is that very few people who tour on a 150cc scooter would plan to spend much time on the interstate but sometimes you just have to get on an interstate for a little bit to get places.  You could certainly ride a Like 150i across the country.  People have done it on 50cc bikes.  Personally I'd prefer a bit more speed for a long cross country trip.

Were very fortunate to have nice paved county two lane roads that run parallel to the interstate so you can just about always find a alternative route. Some of these highways use to be the main highways that went through the small towns before the interstate system and kept in good shape.

[john grinsel]

I think some responders, try to ride scooter like motorcycle=doesn't work that way.  Scooters in US regardless of displacement belong in right lane! Even my 600cc SilverWings.  I find 250 bike or scooter ridden right ok in US.   Going down in displacement does not bother me---1966 went from new Harley Sidecar outfit to CS-90 Honda in Japan.  In 90's went to Korea, took my Concours with me---never used it, my 125cc Daelim scooter worked fine.

Have had bikes that were too slow----Honda Passport 70 in Chicago----MZ 150 passing trucks on Autobahn, left lane (should not have been there in first place!)

Right Lane usually open in US----Americans seem to like to stay left, keeping things blocked.

[klaviator]

I think some responders, try to ride scooter like motorcycle=doesn't work that way.  Scooters in US regardless of displacement belong in right lane! Even my 600cc SilverWings.  I find 250 bike or scooter ridden right ok in US.   Going down in displacement does not bother me---1966 went from new Harley Sidecar outfit to CS-90 Honda in Japan.  In 90's went to Korea, took my Concours with me---never used it, my 125cc Daelim scooter worked fine.

Have had bikes that were too slow----Honda Passport 70 in Chicago----MZ 150 passing trucks on Autobahn, left lane (should not have been there in first place!)

Right Lane usually open in US----Americans seem to like to stay left, keeping things blocked.

It really comes down to what you are comfortable with.  If you are comfortable with the idea of riding cross country on a 150cc, 60 MPH scooter then go for it.  People have done it on 50cc, 35 mph bikes.

[Kansas kymco]

Will agree about people hanging out in left lane impeding traffic instead of using for passing lane.  Kansas passed a law and will give you a ticket for hanging in left lane except in cities.  I was extremely happy when they passed the law and the fact they enforce it.

Then you get two semi's with govenor's on them with one set 2 mph faster and takes 10 miles to pass the other truck. 
I beleive Texas has the highest posted speed limit 85mph.