I THINK THIS ONE IS HELPFUL.
I went through @SafaricomPLC @Safaricom_Care data bundles (with no expiry) and decided to share my findings out with you. The Aim is just to make you understand how a slight change in price affects outcome.

This article is for those who always spend a budget of ksh.10 to ksh.50 on data bundles. Which I believe most of us fall in this category. Check out this @SafaricomPLC @Safaricom_Care bundles prices and price equivalence.
1. Ksh. 9=18mbs
2. Ksh.10=20mbs

3. Ksh. 11=38mbs
4. Ksh. 49=171mbs
5. Ksh. 50=175mbs
6. Ksh. 51= 255mbs
Now my discovery is if you are buying data bundles worth ksh10, you better add a shilling and buy for ksh.11 in that case you will get an extra 18mbs( worth ksh.9) @SafaricomPLC

When your budget is ksh.50, I advice you again to add a shilling and buy for ksh. 51 and in that case you will get an extra 80Mbs (worth sh. 23) just for adding an extra shilling. Avoid careless https://abs.twimg.com/emoji/v2/... draggable="false" alt="👌" title="Ok hand" aria-label="Emoji: Ok hand">spending on data bundles. @SafaricomPLC @Safaricom_Care https://abs.twimg.com/emoji/v2/... draggable="false" alt="😊" title="Smiling face with smiling eyes" aria-label="Emoji: Smiling face with smiling eyes">https://abs.twimg.com/emoji/v2/... draggable="false" alt="😊" title="Smiling face with smiling eyes" aria-label="Emoji: Smiling face with smiling eyes">