Breeding loans can be benificial but as stated before get it in writing! Also take into account are you going to breed your female 2yrs in a row? Or will you breed her to the loaner and then to your pastel the next year. (nothing really wrong with it just something you need to thing about I have not had girls breed more than 2yrs in a row) What if you breed your female to the male she doesn't lay eggs. Then she comes home to your house and you breed her net year to your pastel and when she lays eggs you hatch mojaves and normals? Who's babies are they then?
This can happen and it has happened to me. I bred a mojo and a yellowbelly to a 3 yr old normal that had never laid eggs I picked up late 2009. I bred her late and she laid in August 2010. When the babies hatched they where spiders. I never put a spider in her tub.
Last season 2008-09 I bred my spider male to a normal female that was bred to a pastel the year before (by me). She laid eggs and I hatched pastels. So it is something to keep in mind.