Black Gate caps

I'm curious to know if those of you who have ever modified or upgraded the stock capacitors in their SS preamps to Black Gate caps, could hear a difference or an improvement after the mod. Seems like maybe 2 or 3 years ago when these caps were going out of production, quite a few people were jumping on the band wagon of modifying/upgrading the capacitors in their audio gear to Black Gate's. I'm sure enough time has passed for these caps to break in, so, I'm just curious to know how it turned out for those of you who made the mod, or even for those who have an opinion this subject.. Thanks.