If the gain in resolution with the new column is high enough you could even speed up your analysis by using shorter columns.
How important is scalability for you?
If you use your system for screening and the methods you develop are intended for being easily transferred to a preparative scale HPLC, fully porous particle columns are your best choice. Unlike core-shell columns, a fully porous stationary phase is typically available in different particle sizes (e.g. 2, 3, 5, or 10 µm) and features significantly higher loadability, enabling much easier up-scaling. To speed up analytical throughput under these circumstances, you would prefer sub-2 µm columns, requiring a UHPLC system.
The two aforementioned situations show that it is not just about exchanging the column to achieve higher peak resolution, but also additional limitations and conditions apply, depending on your application and the HPLC system available.
With a UHPLC system or an HPLC system, which can be upgraded to full UHPLC capabilities, you have the choice to master both of the above situations without compromises. The KNAUER PLATINblue UHPLC/HPLC Plus systems offer you that freedom of choice. Be sure to get the maximum resolution with both core-shell and sub-2µm fully porous particle columns.