if you only need 25 then the 25 has a couple of benefits over the 50.  the 25 is lighter, and has channel AND reverb footswitch option.  the 50 only has channel footswitch if you wanted to use without your POD.

aside from that there's very little difference (other than the wattage) and to be honest 50 watts isn't much louder than 25 watts.  in fact 50 watts is only 3db louder than 25 watts which isn't all that much at all.

I have both DT25 and DT50 head by the way.

Rowbi

I have both...If I had to choose, I would take the DT50...It's sounds slightly better to me...the headroom is a factor in that also...Keep in mind, my impression of better sound from the DT50 is a VERY, VERY marginal difference and only when I have my audiophile a$$hole hat on...

tonally both amps are fantastic...headroom would be my only concern...that's pretty subjective as everyone's situation and preference is different...good luck.