To the point of the beer this recipe will make, it looks pretty tasty to me! The advice I will forward on to you that was given to me the first time I went into my LHBS with the intention of using amber extract and I have followed since is this. Often it is very difficult to determine the exact composition of what is in a particular manufacturers amber extract. The reason this could be important to you would be the case where you made an extract beer that was the best you ever had and want to make it again but you are now an all grain brewer and of course you want to convert this recipe to all grain. now not only do you have to convert the base grains that were originally the bulk of the extract, you also need to make a guess as to what the rest of the grain bill went into making the amber extract. An option would be to use all Pale extract, 40L crystal and up the quantity until you meet your color profile in beersmith which is essintially what I did that day in the shop. That's my two cents, but I do really like the recipe you have there as an extract recipe.