Oh, my english is not the best. I just wanted to say that in my opinion it isn't fun to fly such bombers in SFP1 (but it IS in Il-2....) because they simply lack the abilty to fire guns or missiles, and as a target for soviet interceptors they are too rarely available.
The B-58 is already released, but by now it hasn't made it to Combatace.com.
It was made by Pasko, at whose site you can download it (http://home.earthlink.net/~pasko_patak).
In my opinion it suffers the main disadvantage of all non-gunfighting od missile-capable bombers for SFP1. Bombs are difficult to handle, yet there is no bombsight for the B-58. Of course it's a nice addition for SFP1, though as an interceptor target it is rather uncommon.