If the gs-25 is the 36in belt walk behind, my buddy has one and it cuts really nice [particularly at short heights] with its overlapping blades and compact baffled deck. It has also given him very good service reliabilty. Tom
I have a gs30 which I assume is basically the same machine (36" 13hp, however it is a kohler) unless this is one of the new walkbehinds they are coming out with.
I like mine. I bought it at the beginning of last season. It is a very durable mower. I have had zero problems with it, and it cuts pretty good. I think it is a great mower for the $2200 I paid for it (new).
Here is a lawn that I cut with the gs30. Just barely squeezes through the gate. I think I will be adding a striping kit to it this year.