It's always been a running joke about part numbers rather then an actual bad reputation. Plus throw in the fact that he doesn't take online payments and his web site can be a chore to navigate sometimes accounts for people in the hobby to pass on the rumor of a bad reputation.
I've contacted him several times about parts that didn't have part numbers listed and he's always been helpful. I don't like sending checks in the mail so only use him as a last resort. But will say all his parts are of great quality and priced fairly. If he did take online payments he would be my number 1 supplier.