Buy the best you can afford.
Then do yourself a favor and buy some Diemaster by Lenox 1/2x.025x18tpi SR blades when you have to replace the blade! They are about the best in my opinion!!
You will destroy a couple of blades before you learn, what I am about to tell you!
In my opinion lube won't help! You want the blade to last,
don't:
Force the material let the blade do the cutting
Adjust the speed, to fast on the speed is equal to forcing the material
you can cut radius's
BUT and here is the big but, if you cut a tight radius the blade will pick-up a warp and after a blade warps it will continue to cut. However trying to cut a straight/square cut from the time you warp a blade you will constantly have to chase the line. In other words to cut a straight/square cut you have to run the material sideways through the blade.
Always make sure your work is supported, if it binds you will A. break the blade B. chip off a tooth or two!!
Here is my set-up:
Click the thumbnail and it will open to a full pic. If there is anything I can help with give me a holler!