l have a Subaru WRX and my friend is got a Subaru Liberty.l was told by my friend that it is good to stretch out the gears, as long as you do not make the engine scream as it is better for the turbo.Apparently people at Subaru told her this when she purchased the car.She does 60 km/h - 70 km/h at 3rd gear and 80 km/h - 100 km/h at 4th, where as l do that in 4th and 5th gears.
Is this true?l tried doing this after she told me and even though my engine did not scream, l just could not bear the 'loud' noise of the enginethat l went back to my way of driving.
What rpm should l let it get to before changing is good?Is constantly driving at 3000rpms (or just a little bit over) good for the car?
l need to be on a freeway going to work and getting home, so it is ok to be doing 100 km/h and have it on 3500-4000 rpms all the way?

With 3000 rpm your car will get weak after some time and will loose HP.The best Rpm are about 4500-5500.tip for turbo engines.After you done with driving before you shut off the engine let it run for one minute to discharge left pressure in turbo and in engine.Thats gonna keep turbo and engine in good shape.

it actually is good to wind the motor out periodically. say maybe everytime u get on the freeway. l wouldnt redline it. but.. get it high.. reason being, the piston rods will stretch when they get hot, from high rpm. & the piston rings will wear the cyllinder wall down, & if u never run those rpms high enough to let those rods stretch their legs. the wear on the cyllinder walls will create like a lip. at the highest point that they usually reach .. at 3k rpm in ur case. & it will be fine if u always drive the car this way. but u will probably sell the car before the motor goes bad. & the next person, considering it is a turbo, will be running it out to those 7k rpms & that lip that was created from 100k miles or more at 4k topps rpms(your driving), when they run that motor at these higher rpms, that lip is gonna rip into those piston rings when those rods stretch. & make the piston rings go bad faster.

which wont matter to you, but it will extend the life of the car if u sell it to some one who will drive it a little more extremely than you, or u let some one, say ur brother borrow it for a few months ect who does not drive with ur conservativeness..

You r driving conservatively. Why u have a turbo beats the ''H'' out of me. What a waste. Its a hi performance car & u r driving it like a granny.
Yes u can ''lug'' it to death, that is: drive in too high of a gear for the speed u r driving. Grannies wreck engines too. You will blow out the bottom end.
What the red line at? 7? If it is that, do not be afeared of taking the engine up that high(not for extended periods - like 100 miles of highway driving, but shift blips r OK. Cars on average r meant to be driven in at least 70% of the maximum RPM all day long.
You would have done better to have gotten an automatic transmission.

.....REDLINE, DUH!!!!!!!!!!!

Actually when breaking in an engine u never want to keep it at the same steady RPM. A car is engine is designed to run all day long at any rpm & that is why there is a built in rev limiter, cause that is the area they do not want u going into.

Do not listen to car sales people, there is a reason why they r selling & not working on them. And it is not because of money because a good tech will clear more than a sales person any day.

Ignore the fact that it is a turbo. Your turbo is spinning even when u r stopped & the engine is running. Change the engine oil more frequently than a non-turbo & the engine will be fine.