That comes after a useful season at Derby, who finished fifth in the second tier of the county championship.
Guptill averaged 38.35 in eight first-class games, 69.5 in five limited-overs matches, including two centuries, and topped the Derby batting list in T20s with 476 runs at 34.
"It was a fantastic experience, and playing with a great bunch of guys," he said from Bulawayo yesterday.
He's happy with progress but reckoned he picked up one important point out of a lifestyle in which batsmen can be at the crease six days a week.
Guptill summed it up as "don't be too hard on myself; it's only a game", reasoning that the English circuit offers plenty of opportunities to work on his technique.
His only test century, 189, was against Bangladesh at Hamilton last season; four of his last nine innings, against three different countries, have been half centuries.
Consistency has been an issue, which Guptill is aiming to rectify.
In ODIs, Guptill has just two centuries - on debut against the West Indies in January 2009, and last weekend in Harare - in 54 matches, which is a lean return for a player invariably doing his work in the top three.
Back to tests. Australia beckon, with five-dayers at Brisbane and Hobart in the first two weeks of December. Then it's Zimbabwe at home followed by the visit of South Africa.
There's the potential for 14 test innings for a top order batsman, a royal opportunity for Guptill to show that, at 25, he's well past the "potential" label.
First, it's Zimbabwe on what is expected to be a comfortable batting strip next week. Time to cash in, and there should be no surprises from the opposition bowling attack.
Zimbabwe's talent pool is shallow. There is talk that a couple of batsmen New Zealand have not faced so far on tour might be chosen but otherwise the names won't change.
Guptill has been impressed by what he's seen from Zimbabwe, who had pockets of encouraging form in earlier games before showing plenty of spirit in winning the last limited-overs match.
"They've got some good players," Guptill said. "All they need is experience of playing international cricket but they're always improving, they're a lot stronger than in the past, they're on the up and that's good for Zimbabwe cricket."
That said, Guptill fully expects New Zealand - now bolstered by the arrivals of former captain and senior spinner Dan Vettori and veteran new ball bowler Chris Martin - to win the solitary test, and well, "if everyone does their job".
And that starts with Guptill and his opening partner, Brendon McCullum, who has been in equally good touch on tour.
