Chemiluminescent probes info needed

[tronni at nphi.fi]

I am planning to try chemiluminescent probing for Southern
and Northern blots. I would like to get rid of using
phosphorus-32 probes.

Any information and opinions concerning the following
questions are greatly appreciated:

- is there any convenient method to measure the quality
  of biotin-labeled random-primed DNA probe before actual hybridisation?
- how stable are the biotin-labeled DNA probes?
- are there any quality differences between different
  kits supplied by e.g. Millipore, Stratagene, USB etc.?
- how cost-effective are the chemiluminescent probes
  compared to radioactive probes (P-32, S-35)?
- how good is the signal-to-noise ratio compared to radioactive probes?
- is it possible to reprobe the same Northern blot nylon filter 
  with different biotin-labeled probes? My plan is to use three different 
  probes sequentially and to wash away the streptavidin-alkaline 
  phosphatase complex from previous probe before next hybridisation.

Best Wishes,

Tapani Ronni
National Public Health Institute
Mannerheimintie 166
00300 Helsinki