I've used the GM needle roller bearing in several project cars (after dialing-in the bellhousings) with no problems at all. Gotta love the comment above about the needles at 7,000 rpm - there's no relative motion between the needles and the input shaft unless the clutch pedal is depressed; how often does anyone free-rev the engine to 7000 rpm with the clutch pedal on the floor?
The correct oilite bronze bushings work fine too, but take a magnet with you when you buy one, and don't take it if it's attracted to the magnet; there are lots of Chinese counterfeit bushings out there that are mostly iron, and they'll score the input shaft.