If you're concerned with only one tonearm, then I agree with Raul that the Mint LP protractor, which you have to order specifically for each tonearm and each different alignment algorithm you may want to try, is more cost-effective. However, if you're a devoted vinylphile who is likely to own several different tonearms over time, then the Feickert (and many other similar expensive options) makes a lot of sense, too. If you are in the latter category, you made a great choice.
I don't agree with Raul's out of hand dismissal of the Stevenson alignment. Some LPs, especially LPs pressed in the late 50s and 60s, contain musical information right up to or very near to the label; in other words, the run out grooves comprise a very narrow band near the label. For such LPs, Stevenson is worth considering, because its inner null point is closest to the spindle of all the commonly used algorithms. Also, many vintage Japanese tonearms were designed for Stevenson, in that the headshell offset angle is most compatible with Stevenson. For such tonearms, some believe it is best to adhere to the Stevenson alignment. (This is controversial, I admit.)
The best that ANY alignment algorithm can do is to give you two null points on the playing surface of an LP. Where those null points will lie is to some degree be determined by the choice of algorithm. There's no reason to rule out Stevenson, unless you are consistently playing LPs with a very wide run-out area, where the innermost of the two null points afforded by the Stevenson alignment would be wasted.