I have been very happy with my Linex'd flares, while sometimes I miss flares, the finish is thicker than the DIY liners most people use and is completely consistent in texture, and it maintains its color and has not been scuffed whatsoever, even in the CA sun. I took my flares to them and had them spray the exact shape of the factory flares. Personally I think it looks better than tired, JB welded flares that continuously rip off. The best option to deflare is to weld smooth, paint however. The LineX can also be essentially be carefully chiseled and peeled off in strips, but you will need to paint after.
OP if you are looking to line, and the product you are using is thick enough, you can tape off with aluminum tape.