R4I-SDHC.COM has totally released 7 markings cartridges for DSi / DSi XL consoles, and they are R4I-SDHC 1.4.5 on sale, outdated R4I-SDHC 1.4.4/3/2/1, R4I-SDHC 1.4 and R4I-SDHC.
All R4I-SDHC 1.4.X cards share the same official kernel at download page. And they are listed under the column shown as below.
While for the oldes R4I-SDHC without any marking, you need to use the kernel under the column shown as this one instead.
The kernel installation process is same as the one for R4 SDHC, you can follow the guide for both official kernel and YSMenu.
R4i SDHC 1.4.5 supports all current DSi / DSi XL system versions, there is no need to do firmware upgrade for DSi systems.
Moreover, R4i SDHC 1.4.5 could be firmware upgrade for 3DS / 3DS XL. After upgrade, this R4i chip is compatible with 3DS/3DS systems 5.1.0-10A and backwards (Source from r4wood). R4-DS-AU will have your R4i 1.4.5 firmware upgrade for 3DS before shipping out to you.
Other former R4i SDHC 1.4.X do not support firmware upgrade for DSi 1.4.5 and 3DS 5.1.
If you have any questions about using R4i SDHC card, email us at Contact us page.