Large drill bits, made of blued M2 high carbon steel are excellent to use in rust tests. I also use mild steel plate, angle iron, old gun barrels, and 1095 high carbon steel. Coat the metal with the product and spray with a fine mist of salt water several times a day. Sometimes I use good 'ole rainfall as well.
Products that do well in these kinds of tests will normally excel in long term tests as well, unless evaporation is an issue. Salt fog lab tests and water washout tests are great if the manufacturer will release the independant lab test results to the public.
Personally, I rarely use a product long enough to see long term results, with the exception of Break-Free CLP, FP-10 and a few others. Also I don't have any weapons in storage. It either gets used often or it gets sold off in my house.
A friend of mine who does have some fine firearms stored away uses Corrosion-X, with excellent results. He also uses it on his hunting rifles.
As far as compatability with Eezox goes, I never had any problems with it on Glocks. Some manufacturers have tested their products for compatability with plastics, rubber, etc. but many have not and instead leave it up to the consumer to find out the hard way.
Pat Rogers, who has forgotten more about this stuff than I'll ever know, has used Slip 2000 with good results, but I have yet to try any. I have never heard anything bad about their entire line of products.
www.slip2000.com
Clay