Before going ahead, the string hasn't been used on a bass, but on an 8 string guitar. So unless this is exactly what you are planning to do, sorry you gonna have to scroll to the next review.
As mentioned, I bought this XLB090 for my 8 string guitar, it's a Schecter Hellraiser Special with a 26.5" scale and hardtail bridge, tuned a half step down, so: F/A#/D#/G#/C#/F#/A#/D#.
For the first 2 months of owning the guitar, I have used a .080 string thinking it would be a perfect fit. Turns out, at least personally, I required a way thicker string for the low F.
The .080 did not provide enough tension at all, so when I would pick it, the string wouldn't just snap past my pick but keep going with it for a short while before snapping back, which is something I strongly dislike, as it renders my playing somewhat sloppier.
On top of that, because of the lack of tension, the tuning wouldn't hold up for longer than a handful of minutes, say 3 to 5 at best, forcing me to tune over and over again when using this specific guitar, brought me to the point of not doing much 8 string stuff in the last few days until I could change it.
Last night the strings arrived and I could put the .090 on.
I have to say I am incredibly pleased with it, I don't feel I should go any higher, and definitely not lower.
1. Tuning Stability:
Although a .090 might seem not much bigger than a .080, it actually is quite bigger, but not to a point where you are not comfortable with playing it.
Thanks to its thickness, the string stays way better in place than a .080, it doesn't wobbles at all, tight response when picked, and maintains tuning very well.
And for my own joy, no re-tuning almost at all!!! I adjusted of a few cents only after an entire hour of going at it heavily with a pick.
FINAL VERDICT: TOTALLY AWESOME!!!
If like me, you like a good amount of tension, are fairly heavy handed with picking and are using a 26.5" scale 8 string guitar, this string it's perfect for you.
HOWEVER, if your guitar has a longer scale, or you are tuning lower than F, I would suggest looking for a .095 or even a .100.