I bought an 07 manual V8 Vantage a couple months ago after my 2010 manual R8 V8 was totaled.
From a performance perspective, it lags behind the R8 but that's not much of a surprise when comparing a mid-engine sports car to a sporty front-engine GT.
That being said, the performance isn't bad. As others have described, you definitely feel the weight especially during more spirited drives through canyons and the like. I went for a drive on ACH last Friday morning with a 718 Boxster, a GT4RS and a 992 GT3 and got left in the dust fairly quickly through the turns. But I had a great time trying to keep up.
If you want something quick and nimble for canyons and track days, it shouldn't be at the top of your list. If you want arguably one of the most iconic and timeless designed sports cars that still has a good amount of power, performance and engagement (with a manual), I personally think it is a great value for the price they are going for currently. I'd also note it has to be one of the best stock V8 exhaust notes on par with an F-Type R (which I also previously owned).
To be honest, I purchased it as a placeholder anticipating it will take 6+ months to find a replacement R8 while also waiting to see how far the market continues to drop. But in no way am I disappointed when I drive it.
If you're in the market I may be selling it soon depending on how things shake out. One of the best example 07s with only 40k miles that has had extensive maintenance/servicing including an upgraded VAP twin-plate clutch.