Partial Digests:I need advice!

[Heidi Moss]

I am trying to map several human genomic fragments in lambda and would like 
any advice regarding partial digests: is there any trick? What should I 
look for in terms of a "good" partial vs a "bad" partial? I am using 
Stratagene's non-rad gene mapping system which uses T7/T3 oligo probes 
and partial digests to find the restriction sites. 
Any advice would be appreciated!
Thanks!
-- Heidi