Be careful with the word "better".

I have used this tool. It does come up with accurate reforge and gem suggestions. It ignores enchantments, though, which is going to hold it back from finding THE optimal solution for an entire set of gear. In most cases, Mr. Robot provides results with comparable accuracy. I've even found a couple cases where Mr. Robot provides better results - mainly because of the enchants.

As far as picking actual items... there are numerous flaws with this tool. One example is that it does not correctly equate spirit to hit for shadow priests. Another example is that it fails to pick optimal weapons when both 2 handers and one handers are present in the list for casters.

It also has no support for soft caps on stats. This will make it very difficult to optimize certain specs.

So... you might be able to call it "better" for some very specific situations where you want to tweak out that last 10 EP value on your reforges... But if you want a tool that works for all classes, all specs, all gear, and all the nuances of the game - Mr. Robot is going to be a "better" choice.

As I said, it's still starting and needs some tweaks...
The developer is resolving the 2H vs 1H + OH issue as far as I know and some other things. Spirit to hit conversion sounds easy to correct.

About enchanting, also as far as I know, the only issue is hit enchants. You can try subtracting the amount of the ones you might use from the cap to get your results. I agree this is not a nice solution, but it does the job although you might have to run the optimizer more than once... As of the last I read, the dev is not planning on adding enchant support for now (except the OH one), but I do believe he will end up changing his mind at least for the hit enchants although I can't vouch for him...

About soft caps I really can't say... I'm not sure how Mr Robot deals with them either... This surely is unsolvable with only stat weights. If you wanted to deal with this perfectly, you would have to give the program the exact scaling function of said stat and not just a single number. I doubt Mr Robot handles this well but please correct me if I'm wrong.

Most of what you mentioned are either bugs or features that are easily solved/added to make the tool better I think. And if they are, it will probably make it better than Mr Robot for finding the best solution and not just a very good one.

Hmmm, why am I being downrated?
It's not like my intent is advertising, I don't even know the dev guy...

I just suggested it as an alternative and because I think it has great potential. But again: it's still in "kind of" beta...

There is no exact solution for optimizing gear anywhere. Every single gear optimization tool out there uses formulas that approximate game mechanics, simulations that approximate game mechanics, stat weights that approximate relative value of stats. Approximate is the key term here.

Mr. Robot does handle soft caps well. An example would be a class like holy priests. Haste is very valuable to them up to 12.5%, then they don't want it anymore. On Mr. Robot's site you can enter in a weight for haste up to 12.5% and a weight for haste after 12.5%. This will then create a gear solution that devalues haste after 12.5%. This other tool you are talking about cannot do this.

This other tool just does not do anything that Mr. Robot doesn't - it does less. It is strange that you are coming here and saying that people should use an incomplete tool with less features and comparable accuracy.