I too was brought up on torque; I enjoyed a succession of turbo hot hatches over the years and love the shove. I started out with a Sigma Roadsport with the Caterham 140 BHP upgrade. I found this was fun once it was spinning above about 4K revs but below that it was a bit flat. In particular, trundling through a 30mph speed limit in 3rd gear and flooring it at the national speed limit sign was disappointing; a family TDI would leave me for dead till the engine got up the rev range. I was contemplating various upgrades to solve this. Due to unfortunate circumstances I had to sell that and a year or so later, in the search for torque, I got a Duratec 360R. This is a completely different animal, loads of torque and third gear at 30 MPH had loads of shove. Those pesky diesels were no longer a problem, and it was docile and fine in traffic. But it was still flat, it didn't have the drama I was looking for. It was all about the torque curve which was very linear and boring. After several chats with Stuart at Premier Power, I took the plunge and now have a 225 upgrade. It's fantastic, loads of punch low down, a real spike at 5K as the cams "come on" and a pussy cat to drive around town. It's what I was looking for all the time. It is massively quick, licence threatenly so! So, to the OP. The 420 has the torque you miss from turbos. The 310 will have the revs, but may "feel" slower. No seven is actually slow compared to other road users but they are inherently all about how they make you feel. If I was to do it again, I would probably go for a 310 or even a 270 and hand it to Stuart at PP for some of his magic. Lightweight, loads of revs and keep my driving licence!