I am happy with this saw and it has limitations. The limitations are due to the fact that this is an abrasion saw, not a "cold cutting" toothed steel miter saw or a horizontal steel cutting band saw. I have used this saw to cross cut 1-1/4 inch 11 gauge mild steel square tubing without a problem. I use a carpenter's triangle to set the fence to a true 90 degrees. I mark the length with a scratch awl and then cut a pilot cut on the corner of the tubing using an air powered cutoff saw. I then clamp the tubing using the fence clamp and an additional "downward" clamp such that the abrasion blade will enter the pilot cut.
Now repeatable _length_ 45 degree miter cuts are a different beast due to blade deflection and the lack of a solid length stop on a portable saw. You could ask a shop teacher about technique that will enable you to cut two pieces of 45 degree mitered 1-1/4 inch square tubing, corresponding to opposite sides of a mitered rectangle, the same length using this saw.
So this is an abrasion saw. It throws sparks like an Olympic champ. It is loud. It will wake your neighbors. You need a cap, leather gloves, hearing and eye protection. I mean a lot of eye protection. It cuts hot. You will need to grind the edges of the cut pieces.
Blades are much cheaper than "cold cutting" saw blades. This saw is much cheaper that a horizontal steel cutting band saw. No problem as long as you understand what this tool is and how it compares to other methods of cutting square tubing, steel strap or angle iron.
Also consider hanging a welder's blanket to catch sparks and buying a 4-1/2 inch electric grinder with a flap disc to grind edges and welds.