Your better off  buy new if you can .  You buy used your buying someone elses troubles

The Savage is my wife's first bike. She loves it. She was a little concerned with power and weight just like you but I told her  it wasn't that much different as far as weight was concerned. Power is relative to how much do you need or want at the time you twist the throttle.
My opinion is it's a great first bike. What's the mileage and how much does the person want for it?

Check the weights of the bikes you're looking at.

The savage is only 350 lbs.

What's your goal?  Street only, a 250 will be ok.  Freeway, you'll want the 650.

As for power, from the factory it's just right.  Last year I was just a green as you as far as power bikes are concerned.  Yet with a little extra twist the power is there.  Lots of torque to get you started though.

Compared with the Kawasaki 125 Eliminator used by the MSF the Savage is 0.8" higher in the saddle on a 0.4" longer wheelbase.  Due to the larger engine, the Savage is 25% heavier -- 352 vs. 282 pounds.  Not unmanageable, and you get a "beginner" motorcycle that can keep you happy indefinitely.

I bought my '02 Savage in August with less than 1k miles.  My prior riding experience consisted solely of 45 minutes in a parking lot on a '76 Yamaha XS650.  After riding that 500 pound bike in circles my hands were pretty sore from pushing on the bars.  Even though it was for sale really cheap, I didn't feel safe on it.  Instead I found my Savage and 1k miles and a few minor mods later (carb spacer and seat lift), I am very pleased with it.

People tell newbies not to get a big displacement bike not so much because it has too much power, but because that power usually comes with a large increase in the bike's mass, making it hard to handle.  Happily, the Savage is an exception to this rule.   8)

Then again, if you are not trusting a 125... Sounds like a test ride is needed if you haven't already.

   You don't say if your boy are girl and how big you are. In a way a small bike isn't as safe. I started with 200 and 2 month later bought a 550 which was a bigger bike than the s40.To me  at 65 the s40 feel to light.

Dave48 wrote on 12/31/69 at 16:00:11:

While not my first bike, it was my longest riden bike -- a 1974 Yamaha DT175 Enduro (what they now call dual sport.)  Don't recall, but probably under 250 pounds, "freeway legal" but only so I could ride from the campground to the dirt via the interstate.  Stock it topped at about 60 -- I replaced the countershaft sprocket with a pair that gave me top ends of 50 for dirt and 70 for street.  I rode that 175cc two-stroke single from early '74 thru late '86 both dirt and on the streets of Greater Los Angeles.  Never did "out grow it."  Did get a GS450E in the early '80's, rode to Seatle and back to L.A. where it got stolen.  The 175 by then was so ratty I normally left the key in the ignition -- proably could have place a sign on it "Please steal me!" and no one would.  

This time around the dual sport option was not available in a seat height that would allow me to flat foot it; not to mention I don't play in the dirt any more -- maybe later.  So I went for a cruiser.  Just about settled on the GS250 when I noticed the specs on the Savage.  Just 50 pounds heavier, same small size to fit my aging 5'8.5" body -- why not??

If you got the legs for a dual sport and a place to go play in the dirt you might consider something like the 200-250 cc range.  Really depends on where and how you'll be riding.