Here's my situation:
FCS strings on the bass now, and I love the feel of them. I just had the old bridge replaced and the bass has a lot more life than it ever did before, and I'm absolutely thrilled
The problem is, the E on the Flat Chromesteel strings just isn't as warm/loud as the others. To compound the situation, the channel on the bridge which the E runs through was filed down just deep enough to take a string of similar gauge to the FCS string (ie: small). I'm comfortable filing it deeper, but I'd rather not do anything drastic. I tried switching out the E for a Sprio Mittel E this bast weekend, but the gauge was big enough so that it wouldn't sit in the channel...so anything that big is probably out, at least for the moment.
So, I'm on the lookout for a string that is
1. similar in gauge to the FCS strings, as well as that smooth flat feel.
2. warmer/louder (hence, higher tension?) than the FCS in both pizz/arco, but definitely easy to bow.