I've always tried to use the factory 70 degree cam in my road motors, the only time I didn't gave me a motor that needs twin DCOE's just to get a decent idle speed, & doesn't really work til 3500 rpm. I think the 70 degree cams were ground by Wade, but the last one I got seems to come from Camtech in Sydney. Went well with a single DGV & extractors & electronic ignition. I was going to use the latest one in the A15 I'm going to fit to my Sunny Wagon, until I decided to keep the standard cam. That's if it'd stop raining.

Factory? Do you mean the Nissan Competition 70 degree cam? 13001-H5710

Camtech in Sydney I believe also has a Cam Doctor old school these days but well worth putting any cam on as it will give you the lift on number one inlet valve at TDC for correct cam timing which is a hell of a lot quicker than spending hours with a degree wheel.
Example with Grind X the Cam Doctor will give you a figure of say 225 thou lift (Well they were an American invention after all) at TDC number one cylinder and when done that way the cam timing will be spot on because the Cam Doctor measures everything with both a linear encoder and a rotary encoder to check exactly what the grind is, It can also make sure the different cylinder lobes are all indexed correctly to each other.
It and other ones such as the Andrews one really tell you if the cam grind is good or not.

just my 2c - you'd have to do pretty well to top the service and workmanship of clive cams. A class act. some years ago there was a big dustup on moparmarket.com forums due to a bunch of lifters that were produced completely flat (they need a slight curve to 'work' and rotate during operation). Many cam companies sent them out as is and one in particular wouldn't even acknowledge the problem let alone help the customer. Never happened with clive as he actually checks stuff like that before supplying them. They are a very very very well respected firm in mopar circles for whatever it's worth, and the only place I'll now deal with for practically anything. GEtting the right profile is of course important, but it's obviously just as important that the item perform and last the distance too. That you can be sure of with them.

General advice - if in doubt go for the milder of any 2 grinds suggested, and when it comes to lobe separation angle, usually if unsure a fraction tighter (within sane limits) will lose less overall and a fraction too wide either side of whatever might be optimal for a given combination. But that's just my experience, and what I've been advised of, not etched in stone.

and whatever you do, follow cam pre-lube and cam bed in procedures to the letter. I can't stress that enough. It's truly make or break as far as that goes. Don't let a brand new cam sit at idle, you can wreck it quick smart.