Flux core is decent stuff. Honestly, I don't want to bother with shielding gas (and the 101/1 doesn't have a gas hook-up) so it is all that I use. It's more expensive, and it throws a lot of slag (molten metal), but the welds are strong and, with the right technique, they look pretty good, too.
I've also talked to professional welders and they told me that, at least for beginners, flux-core is the way to go.
Just one word of warning: with all the slag that flux-core wire throws, you WILL get burned, it's not a maybe. So, if you have a low pain tolerance, you might want to have someone do this for you.
Oh, and I just thought of one more little problem with that welder. The wire feed mechanism gets sticky sometimes. It uses to rollers that are pushed together and use friction to push the wire through the gun (think of the old clothes ringer-outers in cartoons where the guy gets pulled through and rolled out as flat as a pancake*). The rollers are pushed together by a leaf spring. After a lot of use, the spring can fatigue so that it doesn't hold the rollers together as well. To fix this, just bend the spring so that it pushes more on the rollers. It's not a big deal because you will probably only need to do it once or twice, it's just that it gets annoying because the wire feed becomes erratic.
So, if you're using it and the wire feed speed gets all messed up and you've still got plenty of wire, just bend the spring.
*kinda-sorta-something like this - use your imagination