Engines are tried and tested tech. 3 cyl opti is quite quiet too. Not the lightest of units for its power, but not an issue on a 570 Valiant, it's a big enough boat.
Hull isn't a deep V I don't think, but whilst that means it's not as good as some in rougher weather, and has a shallower deck typically (you sit more on than in) it'll use less fuel and be faster. That's not to say they aren't any good in the rough, it's still a v hulled RIB!!
They're a mass produced unit rather than a small low production hand built British brand. Saying that, they're sold and used a lot and have a fairly good name in that market.
As such there'll be a dealer near you, so go test one out, then try a deeper V hull and see if the difference is worth it to you.