What should I get for my first sport bike?

I have been riding an old 1975 175xl Honda enduro for about a year now so I wouldn't consider myself a beginner but I I've been hearing that the 250 ninja is a great beginner bike and this will be my first Sport bike so this is the bike I have been looking at. Is this a good idea or will I go out grow it too fast?
I'm about 135 pounds and 5'4
My price range is under 3000$
I'm open to any advice

Tom, and most motorcyclists, call middleweight motorcycles to be "beginner" bikes. For them, 100 mph is too slow. They tell you that you need at least a 500cc, prefer a 650, and suggest at least a 1000 to be happy. They will tell you that the 250 is *not capable* of freeway and back country cruising. I know the truth -- "It is more fun to ride a slow bike fast than riding a fast bike slow." Means you don't need to go 20 mph over the speed limits to have fun.

I ride a Vespa LX150, on the freeways, Interstates, touring 370 miles between dinner and breakfast. I admit I can only do 64 mph -- but it is capable. I had a '74 DT175 and mine would do 65mph. Your 175xl Honda enduro is 50-State freeway legal. Depending on your sprockets, your bike can do 65+ mph.

The Ninja 250 is light, easy to ride, agile, capable of 100 mph.
The Ninja 650 is 70 pounds heavier and capable of 140 mph.

Question: What should I get for my first sport bike?
Answer: Depends on what you want out of a motorcycle. Do you want an agile sporty bike, or more top speed?

If you have been riding for a while, I would suggest more the Ninja 650R route, or any of the other 500-650cc VTWIN bikes.

While the 250R and the newer 300 Ninja bikes are fantastic rides (I started on a 250R) you do grow out of them quickly. I would guess even more so if you already have riding experience. However, since you are a fairly small/lightweight person, you could probably get more out of the 250R/300 than I did as a 210lbs 6'0 male.

It also really depends on what you plan on doing with it. Local traffic? Don't need more than a 250R. If you plan on doing traffic, freeway, and some back country cruising? A 650R would be better for you. If you plan on doing more local, freeway, long distance riding? You will want to start on a 650R and probably eventually move up to a Ninja 1000, Concours, or other adventure/sport-touring type bikes.