I had a DT25, and still have a DT50, and just got a Catalyst 100. If you're in a band with other high end guitar amps, I would go for the DT25 or 50. The have great tube tone with the Helix, especially since you can run a AES/EBU cable and run the Helix amps into the DT25 power amp directly. Plus using Helix Edit, you can configure the output stage of the DT to match the Helix amp- Class A or AB, Fender, Marshall, Vox, Mesa topology, and Triode or pentode mode. I've been doing this for years and it's awesome.
That said, the DT amps are heavy, and the Catalyst is light and sounds very good, so the decision is ultimately yours.