Sure I would like to own a G25 or G27, and maybe I could get better times with such kit - I don't have the DFGT,, but have a DFP which is more or less the same kit, so I will throw a few comments in here based on that. I was very lucky to pick my DFP up for £34.99 delivered (new) from Amazon a year or two ago - its the first FFB wheel I have owned (used a MS Sidewinder and a Ferrari Thrust (think thats what it was called) and the first thing I noticed was that I actually found the FFB slowed me down! Others may disagree, but I put it down to a combination of me being able to 'plough' through corners, kerbs etc on the non FFB wheels without feeling or responding to the effects of FFB and also that I suddenly found myself responding to feedback through the wheel as I would in a real car ie, making minute corrections to what I felt before I actually noticed visual cues of the car becoming unsettled (if that makes sense)
I think the DFGT/Pro are cracking value and have fantastic build quality (when you consider the pricing) - That said I do think I could be faster with a G25 or 27 - not because of the build quality but because :
1) I would have a clutch pedal and although I accept auto is probably quicker in changes there are times when I feel a clutch pedal could make me smoother and maybe faster.
2) The gear stick - I use the stick shifter (shift buttons on the back of the DFGT/Pro Wheel are useless if using more than 360 degrees of wheel rotation), now this works well but is attached to the right side of the wheel and is only sequential - I think I could do better if I was able to reposition the shifter to work better for me that could mean higher, lower, further forwards/backwards or even to my left (bearing on mind in the UK we drive on the Left side (which is the right side of the road to drive on!) and our cars are mostly right hand drive meaning in the UK for most of us in real life the stick is to our left and is operated with our left hands, so using our right hand can be a bit odd at first.
In summary its a great wheel and as in real life you'll get used to how the pedals work and where the gear stick is quite quickly and for gaming I'd highly recommend it.
Unless you have G25/27 money to spare, then I'd say get one of these - IMHO - Its not about being faster because your kit makes you faster its about IMMERSION - and if the Kit gets you more Immersed and the experience feels more realsitic then your probably gonna perform better because of that Immersion and that should lead to faster laps - but then again I'd pick slower laps and Immersion over faster laps any day.... In real life I'd be Immersed anyway so of course would always choose the faster laps!!!