Flux core welders dont weld pretty, but they get the job done, as long as its a small job. You wont be building any trailers with one, thats for sure. Muffler work, small brackets, body work, frame repairs, 4 wheeler/atv stuff, and the day to day things from just being a guy who owns a truck and breaks a lot of things, a flux core is great.
I have a $700 lincoln mig welder, add 500 for a spool gun to weld aluminum and 300 for tanks and shielding gas and I have over $1500 into mine, and all I use is flux core wire. Go figure. I rarely use over 80 amps and I think the welder you mentioned is 90 amps. Get it, use it, and when you get ready, sell it for about $20 less than you paid for it to get a bigger one.
If you have never welded before then start saving up scrap metal to practice with. Its all about wire speed and amperage, the rest comes with practice.