"The South African teams have won one game in the UK out of 25," said Pivac.
"The Cheetahs win at home at altitude, but the Kings haven't won a game all season.
"You can't judge it too much from that. But there are so many ex All Blacks and Super Rugby players from Australia and South Africa.
"There are a lot of New Zealand coaches who bring the New Zealand traditions, techniques and tactics with them. There are New Zealand coaches scattered throughout the three (professional) competitions."
Pivac — who has been linked to the Welsh coaching job when Warren Gatland retires after the 2019 World Cup — said it was difficult to make a complete judgement when there was no contact between provincial sides from Europe and New Zealand.
"But I think it is a strong level of rugby here," he said.
"We saw what a lot of these players did with the Lions in New Zealand, they weren't a walkover.
"In the November autumn series, the All Blacks had a couple of really good games against Scotland and even Wales for most of the game. I think the gap has closed a little bit, which is great for rugby.
"It's quality rugby - the northern hemisphere rugby is improving and it is going to be very interesting later in the year when the All Blacks come back up."
Pivac described Llanelli as a "community club" with a small budget by European standards. Yet it was still a big money operation which included a heated main field and indoor/outdoor training venues.
"Llanelli is about the size of Whangarei and (the club) has a few hundred sponsors rather than a few big ones," he said.
"They're fanatical...people stop you in the supermarket and tell you who should be playing, who shouldn't, what you are doing wrong and right.
"The big difference is the length of time you have with the team. There is one team in three competitions so you are together for 11 months of the year which is quite a grind.
"My budget is in excess of five million pounds, with a squad of 50 players, and 25 management. It's serious stuff."