is it a good idea to buy the sleeves from JG or Darton, and just let another shop install it to my block?

i know it sounds stupid not to let the original shop of the sleeves install them in my block............and letting another shop to do it for me. But my car is in another country, and i want to buy internals here (pistons, rods, and sleeves)........and let my tuners over there do blueprinting, and a machine shop install the sleeves. I am just wondering, what are the disadvantages, if I buy Darton or JG sleeves, and let another shop install it into my cylinider?

thanks!

 

without the sleeves..............is having the block guard be enough to have a strong bottom end? or the sleeves will be the one that make the bottom end...bullet proof?