Are 45-105 gauge strings good enough for Db-Gb-Cb-Fb tuning?

Are these good or should i go for a 50 70 85 105 gauge?

You're talking dropping everything down three half steps, correct? If you have a set of 45-105 on your bass right now, give it a shot and see how it feels. If it's too floppy, then try a 50-110 or 50-115 set.
 
Agree with @Jon Moody. GHS used to make a 'Big Core' set that I liked, but it is discontinued. I would suggest a heavier gauge and hex core for drop tuning. The heavy 50-115 hex core Bass Boomers fill the bill. Plus GHS uses a heavier hex core than other string winders.
HeavyBoomers.jpg