If im correct thats a Class 150. Great Western Railway run trains on the upcoming Penzance to Truro & St Ives. Personally I would love to see the class 800/802 on there too, iv only been on thoes trains twice but they were amazing. I think we all need a modern GWR route, so the class 150 and 800/802 would be perfect for this route.
It's a 158 - they are OK, nothing special though. Curious about that picture though as that appears to be tube stock in the background!