I had Waggoner on my visit in September. I have to say, I wasn't impressed. The vintage carriages, they made for a more interesting trip. Unusual to be on something other than MK1s on a preserved railway, something pre-BR was quite interesting.
In terms of the line, a case of 'Meh' applies. Not terribly exciting to be honest, and a case of 'do it to get it in the Baker' for me. Not even a 37 would have made it more interesting I reckon.
You'll love the 38 stock, if you're owt like me. It can be be a bit bouncy, but as a Pacer man, you'll be used to that
They make a nice bit of noise and they're certainly more interesting than I thought.
Either way, enjoy your trip to the IoW. Are you indulging in the monsterously awesome hovercrafts? I'd say they're well worth a go, and if you're coming back the same day you can get a day return on Hovertravel combined with a day's unlimited travel on Island Line trains for £15.50. An absolute bargain, and so much more fun than a convential ferry!