While Rudy is a social RINO and anti-gun, he has shown himself to be a loyal supporter and defender of more conservative Republicans, and I think he could be counted on to hold the party line on nearly every key vote in the Senate.
Also, while he doesn’t agree with the GOP on some key issues, I’ve never heard him talk about moving the party to the left to expand it. He seems to understand that he is the outsider who needs to try to fit in, rather than trying to change the party to suit his own beliefs.
As a New Yorker, I’d rather send a true conservative to the Senate, but Rudy might be the best we can do, and would be a huge upgrade over any Democrat.
Bottom line. Rudy would be a definite gain. The purists around here need to recall the dictum of Ronaldus Maximus that if someone votes with you most of the time, he is your ally not your enemy.